Add Bazel target for the Objective-C protobuf runtime

Also add WKT headers to the umbrella file, and simplify Podspec with it.
Plus some layout improvements to the BUILD file.

Implement parsing for proto3 primitive repeated fields.

MinGW64+MSYS2 compilation issues

Delete default UnknownFieldSet when shuting down.

Fix "sometimes-uninitialized" warning on Windows Clang.

fix compiler warnings.

Enable tests for bazel build.

- control reaches end of non-void function.
- remove a deprecated IsMatch.

Change-Id: Ifdeb15879bbcf591c48dc7fda1cd8994bdf87bb3

fix typo in cmake/README.md

Update upb to fix two bugs in the Ruby library.

Fixes:
  https://github.com/google/protobuf/issues/502
  https://github.com/google/protobuf/issues/425

Add nonnull/nullable/null_resettable markup to ObjC library.

Change-Id: I63ed5fb58a45e098f2fd1fa457a219148de030bd

Remove OUTS constants in BUILD

Induce those from the input proto file names instead to reduce the
lenght of the BUILD file.

Change-Id: I1dda57dedac547f4bd0cc3a7d08fb611d72acd13

Update BUILD for the recent json util change.

Change-Id: I0b5a2c017f5412aaca3a47815671753cdef63165

using ::isnan to avoid conflicts with std::isnan for C++11 build.

Change-Id: I057b44eff04c3b0062a4fd4307ce6e4ca1eb952b

Change-Id: I74e2d5958b5e7b15d10e5a6468bca917323b9739

Add bazel support for the project

Change-Id: I62640af99e3c2650a29dc5468ce3deb7b6c7efdf

Change-Id: I5a299d969ff96d7d2f80aadc7e8987d461d24b8f

Change-Id: Idecb2e3a5169f7b40d832242c9c10b0eb4325654

Down-integrate from internal code base.

Check HAVE_CONFIG_H before including "config.h"

Now the Build tool needs to define -DHAVE_ZLIB and -DHAVE-PTHREAD rather
than providing a config.h

- Make pbconfig.h a manually written file to handle hash conditions
  according to platform related macros.
- Remove #include "config.h" from source code.
- Changed the configure.ac and Makefile.am to pass down the macros.
- Change cmake to pass down the the macros.

Change-Id: I537249d5df8fdeba189706aec436d1ab1104a4dc

Add the clang annotations to the objc library and generated code to help with Swift bridging and compiler checks.

[ci skip]

Change-Id: I9391c09640e0b0b2b21c45a97a1fc91814d95c5d

proto3 primitive repeated fields, packed data cannot be parsed if
definition is unpacked. Neither is the other way.

Add a badge for AppVeyor build.

Modified FindRubyTestDir to use GOOGLE_THIRD_PARTY_PROTOBUF

Change-Id: Ic59d78d699af0e5f50377f83c8a7ea9a78074d81

Remove config.h.include which is no longer needed