C++98 (stlport) support for core FlatBuffers and FlexBuffers.

* Added internal - limited - implementation of flatbuffers::unique_ptr
  for STLs that don't ship with std::unique_ptr.  In C++11 and beyond
  this is just an alias for std::unique_ptr.
* Aliased used type traits structs is_scalar is_floating_point is_unsigned
  into flatbuffers namespace so they can be replaced in C++98 implementations.
  Right now these point at stlport's TR1 implementations.
* Wrapped vector::data() in vector_data().
* Wrapped vector::emplace_back() in vector_emplace_back().
* Wrapper string::back() in string_back().
* Added variants of FlatBufferBuilder::CreateVector() and
  FlatBufferBuilder::CreateVectorOfStructs() that allow the use of plain
  function pointers.
  Generated code has also been modified to use plain functions to build objects
  rather than std::function() so all generated code will work in C++98
  applications.
* Added flexbuffers::Builder::Vector(), flexbuffers::Builder::TypedVector()
  and flexbuffers::Builder::Map() methods that allow the use of plain function
  pointers.
* Changed Parser to internally use plain function pointers when parsing table
  and vector delimiters.
* Added specializations of NumToString() for 64-bit types that aren't supported
  by stringstream in stlport.
* Overloaded numeric_limits for 64-bit types not supported by stlport.
* Replaced build_apk.sh (which was broken by deprecation of the
  "android" tool in the Android SDK) with build.gradle and the
  appropriate gradle wrapper to build an APK.
* Switched Android build to build against all STL variants.
* Updated travis configuration to build Android test and sample.

Tested:
* Verified all tests continue to work on Linux, OSX and Android.
* Verified Travis build is green.

Change-Id: I9e634363793f85b9f141d21454b10686020a2065

* idl_parser.cpp ignores $schema in input json
#4381

* idl_parser.cpp: Fixed ci error signed unsigned comparison

* idl_parser.cpp: replaced case insensitive search for $schema with case sensitive search

* idl_parser.cpp: Expecting a string constant after $schema
#4382

The ByteBufferFactory interface gives the user an option to specify
the method in which the internal ByteBuffer is allocated. This provides
flexibility in the type of ByteBuffer that can be used.
The sizedInputStream method is an alternative to sizedByteArray that
does not make a copy of the data in memory.

* Added empty generator for json schema (idl_gen_json_schema.cpp)
#4360

* JsonSchemaGenerator: output of tables implemented

current problems:
- typenames are not correct
- array types need to be deduced

#4360

* JsonSchemaGenerator: Corrected generation of typenames
Current problems: enum types not written correctly
#4360

* JsonSchemaGenerator: Added generation of enum types
#4360

* idl_gen_json_schema.cpp: Write required properties to schema
#4360

* idl_gen_json_schema.cpp: Export Types including namespace
#4360

* idl_gen_json_schema.cpp: Fixed Json format
#4360

* idl_gen_json_schema.cpp: Formatted according to google code style
#4360

* Checked in monster_test.bfbs with changes from master

* Added idl_gen_json_schema.cpp in CMakeLists.txt

* generate_code.bat: Added generation of json schema

* Added todo.md

* generate_code.sh: Added generation of json schema

* Addressed some review issues
- removed command line arg -S
- removed new lines
- fixed codestyle in template functions
- removed usage of stringstream
- idented json schema
#4360

* removed auto in idl_gen_json_schema.cpp

* idl_gen_json_schema.cpp: changed iterator declarations to auto
#4360

* deleted todo.md

* idl_gen_json_schema.cpp: Removed keyword "override" so that vs2010 can compile

* idl_gen_json_schema.cpp: switch statement in GenType handeles all enum-members

* idl_gen_json_schema.cpp: Removed cerr output

* idl_gen_json_schema.cpp: Avoid vector copying

* idl_gen_json_schema.cpp: Fixed identation of json schema output

* idl_gen_json_schema.cpp: Do not output empty descriptions

*Keep legacy compatibility with StandardCplusplus lib (utility.h)

Change-Id: I0da57cc71318ea13c10b547e2dfe3a2d4f32b4d9
Tested: on OS X.

Change-Id: If2802ca48b61cfa7e5ec131e2a268400523217e2

This gives a 10x speed up in my test, when creating a Vector of floats

Change-Id: I4610946ac27d9d0d73c2fc2e4834bd2cfed88cdc
Tested: on Linux.

Change-Id: Ie28fd1f0b463aac23647d38921600f15c8b7c10a

Change-Id: I955b4b3eed27f26773d7dc0acceff13c88d1333d
Tested: on Linux.

Change-Id: I9d71375059369fbc538d0d051d8d2885e467bf29
Tested: on Mac OS X.

Change-Id: I48d41a240c8bf362b1f931f20a3ed9ae64f2d295

flatbuffers.h(591): error C2220: warning treated as error - no 'object' file generated
flatbuffers.h(591): warning C4267: 'return': conversion from 'size_t' to 'flatbuffers::uoffset_t', possible loss of data

SerializationTraits<T>::Deserialize _transfers_ ownership of the buffer,
so we must destroy it.

This commit also includes some misc fixes:
- Use grpc::Status::OK rather than default ctor for clarity.
- Check for a null buffer passed into Deserialize, and handle it the
  same way as the protobuf deserializer.

FlexBuffer parser is just 40 lines of code (on top of existing parser!).

Change-Id: Idebebadafb661ca5333f5621139031f6df3c3e1a
Tested: on Linux.

Change-Id: I918b66eb5646d035e3aae675f745802eb54b03ea

* Extended json parsing capability: add support for parsing nested lists and top level lists

* Stylistic conformance with surrounding code + generalized comments

* More code tidy-up for stylistic conformance with surrounding code

* Blank lines

* Reverted changes related to top-level list parsing

* Styling: newline before else

* Taking out ProcessTableFields which is no longer needed as the top level list change was reverted.

* [C++] Remove std::iterator usage (#4340)

Inheriting from std::iterator has never been required, and it's
deprecated in C++17. It can be replaced by directly providing typedefs.

Include <iterator> for std::random_access_iterator_tag.

Note that structs default to public access control.

* [C++] Change whitespace style in typedefs.

* Rework flatbuffers + gRPC integration

- Introduce `flatbuffers::grpc::Message<T>`, a `grpc_slice`-backed
message buffer that handles refcounting and allows flatbuffers to
transfer ownership to gRPC efficiently. This replaces
`flatbuffers::BufferRef<T>`, which required a copy call and was also
unsafe w.r.t. buffer lifetime.
- Introduce `flatbuffers::grpc::MessageBuilder`, a gRPC-specific builder
that forces a `grpc_slice`-backed allocator and also adds some helpful
`Message<T>`-related methods.
- Update serializers accordingly (now zero-copy between flatbuffers and
gRPC).

* gRPC: verify messages by default, but allow user to override

* gRPC: fix some formatting issues

* Disable verification by default, but add helper method

* Make FlatBufferBuilder fields protected + remove vec accessor

* Use bool add_ref parameter to toggle refcount incr

* Remove unnecessary inline specifiers

* Fix formatting

* Use auto

* Remove empty lines

* Use grpc_slice helper macros

* Simplify reset code

* Disable Message copy ctor and assignment by default

* Remove unused member

* Enable gRPC verification by default

* Use auto

* Bake in message verification (remove template specialization)

* Add RoundUp func

* Consolidate gRPC message copy flag

* Make vector_downward allocations fully lazy

* Test message verification failure code/message

* Add grpctest verification test comments

* Simplify reallocate implementation

* Make initial_size a size_t

* Use ternary op for growth_policy

* Use truthiness rather than dont explicit nullptr check

* Indent preprocessor directives

* Remove grpc message copy/assignment

* Fix a few bugs

* Add gRPC example

* Add basic gRPC docs

* Use doxygen EXAMPLE_PATH + @include

* Reference example fbs in grpc docs

* Move gRPC examples into grpc/samples

* Fix pointer/reference formatting

* Use std::function rather than templated callback func

* Create fresh message builder for each request

* Use Clear() in Reset() impl

* Use FLATBUFFERS_CONSTEXPR

* enables "for each" logic on enumeration types

* Remove std::move around a raw pointer

Calling std::move on a raw pointer has no advantage to just copying its value. Moreover, it is confusing, because it indicates that the argument is movable in some non-trivial way (e.g., is it actually meant to be a smart pointer?). More context in https://crbug.com/729393.

* Remove the move constructor altogether

Change-Id: I4b5d822cc4eda975949d1b7cf33674c5bbf9d4b1
Tested: on Linux.

Also fixed that the parsing test wasn't calling the buffer
testing function.

Change-Id: I5baae071bf0832c7797b4ef1d19d9b015e3ff5bc
Tested: on Linux.

FlexBuffers are actually completely unrelated to FlatBuffers and can be used separately.
However, since they utilize several utility functions from flatbuffer.h, they require this header file, which creates unreasonable dependency.
By moving those utility functions to separate base header, both libraries can use same code but still be independent

* Track included files in PATH-agnostic way.

Use full paths as keys in the map of included files. Store logical
include path as a value, in order to put it to the generated file.

* Fix tests by accepting null |include_filename|.

* Fix self-includes code generators.

Changing to keep include prefixes had two side effects: the main
file being parsed wasn't filtered out anymore, and include directory
paths would be added to the path in the include statement.

Also moved the include_test*.fbs files to sub directories so we
can actually test the handling of -I etc.

tested: on Linux.

Change-Id: Ibae095cea7ab0cccbac15cfb5171719f6b5cad8c

* Improve Allocator handling

- Templatize Allocator on vector_downward, and make it own the allocator
instance so it can manage lifetimes.
- Templatize + rename FlatBufferBuilderT accordingly, and add a typedef
to FlatBufferBuilder so old code continues to work.
- Fix some issues with the release deleter
- More details in github issue #4311

* Fix constexpr for older MSVC

* Reimplement allocator improvements via inheritance

Instead of templates, use an abstract base class and some unique_ptrs to
implement the new and improved allocator.

* Fix misplaced newline

* Add missing override keyword

* Add macro for func delete to support older compilers

* Explicitly move BufferDeleter (maybe fixes VS 10?)

* Revert previous attempt at VS10 fix

* Try yet another workaround for MS 10

* Use FLATBUFFERS_NOEXCEPT macro

* Add FLATBUFFERS_OVERRIDE macro

* Fix some issues with MSVC 16 hack

* Remove dep on unique_ptr

* Update DEPRECATED macro with a message

* Sigh, no delegating ctors before c++11

* Fix simple_allocator stub

* Relax FlatBufferBuilder ctor

* Add vector_downward reset + assert in clear

* Rename DetachedBuffer to FlatBuffer + remove unnecessary deprecations

* Add flatbuffers::FlatBufferBuilder::Release()

* Address remaining allocator-improvements comments

Change-Id: I7914c88ad7b31baa7586771423069dc2b90d534f
Tested: on Linux.

There were several possible bugs involving paths not being
recognized as being the same on Windows. Rather than trying
to ensure all code deals with / and \ correctly, paths now
get transformed to / on input, fixing all current and
future such bugs.

Tested: on OS X.

* Eclipse ignore

* TypeScript support

* Prefixing enums

* Test results

* Merged JS and TS generators

* Fixed AppVeyor build problems

* Fixed more AppVeyor build problems

* Fixed more AppVeyor build problems

* Changed TS flag to options struct

* Storing options by value

* Removed unneeded const

* Re-export support for unions

* Uint support

* Casting bools to numbers for mutation

* TS shell tests

* Reverted generates js test file to original version

* Backing up js tests and properly generating test data

* Not importing flatbuffers for TS test generation

* Not overwriting generated js for tests

* AppVeyor test fixes

* Generating the most strict TS code possible

* Not returning null when creating vectors

* Not returning null from struct contructors

* added check for presence of required fields.

* updates to resolve Travis CI build error.

* fixes for resolving appveyor build errors.

* fixes for resolving appveyor build errors.

* fixes for resolving appveyor build errors.

* updates per aardappel's comments.

* updated a variable's name.

* updates per aardappel's comments.

* Added <autogenerated> in cs generator file header comment
#4287

* CS: Added xml-correct file header comment including "<auto-generated>...</auto-generated>"
code_generators.cpp: FlatBuffersGeneratedWarning() function replaced by compile time constant "GeneratedWarning"
 also removed extra newlines at end of GeneratedWarning to be able to generate a xml well formed file comment for cs files
#4291

* code_generators: Changed static string GeneratedWarning back to function FlatBuffersGeneratedWarning()
#4291

* Added modified Unit-Test files
#4291

* idl_gen_general: Add autogenerated only in C# code
#4291

Change-Id: I9629a7648f0c3346c4724ca8938fed47d7828018
Tested: on Linux.

Since it wasn't documented and very different from a vector of
tables, this has caused a lot of confusion in the past.

Change-Id: Iab47c61b55c19abe5c4f25c86d71335a6b6321ca

Previously, we had a check to simply skip such files, but this
tends to make build systems unhappy.

This only affects C++ and JS, since other language output per-class
files.

Change-Id: I54224642725bbafb9f6e1654ed3693e62ca9f7d7
Tested: on Linux.

* Fix C++ code gen indentation when empty Print

* Also commit modified tests/monster_test.bfbs