Update cmake/README.md for #783 PR

VS2010 compatibility of address initalization

Add missing csharp_doc_comment.cc to protoc_lib.

Used static cast to improve initalization compatibility with MSVC2010

VS2010 cannot compile json_util_test.cc since it assumes NULL as a zero (int), and therefore cannot convert into to char*

Support ToString in RepeatedField and MapField.

Generate well known types for python.

Integrate google internal changes.

Add "java_proto" target in bazel BUILD file to provide Java runtime library.

Extract XML documentation in a primitive but reasonably-effective way

Support enum forward decls in Objective C++

NS_ENUM changes defintion in Objective C++ based on the C++ spec being
compiled with, special case the one situation where it wouldn't support doing a
forward decl for the enum.

This changes how we approach JSON formatting in general - instead of looking  at the field a value came from, we just look at the type of the value. It's possible this *could* be slightly inefficient, but if we start caring about JSON performance deeply, we'll probably want to rewrite all of this anyway. It's definitely simpler this way.

When we support dynamic messages, we'll need to modify JsonFormatter to handle enum values, as they won't come be "real" .NET enums at that point. It shouldn't be hard to do though.

This could be tidied up significantly, and at some point we will want to parse the markdown and generate more appropriate XML - but this is definitely better than nothing.

Generated code changes coming in next commit.

Cleanups for newer Xcodes

Add (some) XML documentation to generated code

Fix Podspec version number

- Move up to 8.4 as the high simulator (assuming Xcode 6.4).
- Add cast to NSMutableDictionary so clang and resolve the selector.
- Add case for the newer static analyzer so it won't trigger a false warning.
- Update the "dictionary" interface to use "object" naming. Xcode 7+ has gotten
  more strict on the use of nonnull/nullable; combining that with the generic
  collection support; and the "dictionary" classes we created now collide with
  what the generic KeyValueCoding in the system headers triggering
  warnings/errors. Fix this and hopefully all future issue by renaming the
  methods to use "object" for the classes that have data types as objects
  instead of PODs. Taking this renaming hit now while ObjC is still in beta
  because it is a breaking change for any existing code.

library.

A very small fix to silence some warnings.

This was released as `3.0.0-alpha-4.1`

(Generated code changes coming next...)