Previously, extensions with field numbers greater than 268435455 would
result in a compile time error in generated code that looks something
like this:

Foo.java:3178: error: integer number too large: 3346754610
                3346754610);

This is because we were trying to represent the tag number (an
unsigned int) using a java int constant, but java int constants are
signed, and can't exceed Integer.MAX_VALUE.

Fixed by declaring it as a long instead, and casting it down to an
int in the implementation. This is safe, because the tag value always
fits in 32 bis.

Change-Id: If2017bacb4e20af667eaeaf9b65ddc2c30a7709f

A few fix-ups for protoc-artifacts

Include all well-known type protos.

Change-Id: I122f1cee71a8a739ea603e52582cb0fa9698f0ed

1. make google/protobuf/stubs/pbconfig.h before making protoc, otherwise it
won't build a freshly checked-out code.
2. Document the build environments that have been tested to work.
3. Add support for MINGW64

This is necessary for testing on iOS.

Change-Id: I54ec1e3aa2e9fbfff9a6cd6580920a6a62069b63

Fix for issue 283: JSON handler cleanup typo causing segfault.

Includes repro test case from @wfarr.

Migrate Python tests to stdlib unittest, drop apputils dependency.

Use stdlib's 'unittest' instead.

We already run all tests with and without `--cpp_implementation`

Added Python to Travis build and clarified setup instructions.

Process to deploy artifacts for multiple platforms into a single release.

Remove useless file that doesn't load

This file was broken in ada65567.

Change-Id: Ib75664194491643f8e4f1503a2ed942a2d1e1655

release.

- Do not close the staging repository automatically
- Added staging.repository property
- Updated README with instructions for deployment
- Fix building 32-bit Mac artifact

perf: String#getBytes(Charset) vs getBytes(String)

Better support for cross-compilation