fix php generated code test server port

Adding 2 helper build scripts to allow docker images to be built

Unref the slices if no write will happen.

More scalable unary polling

Refactored benchmark reporting mechanism.

Flush printers in protoc plugins properly

from local repositories.

Framework is already set up in private_build_and_test.sh; helper build script
is needed for each langauge.

Fix for changed parseFromData: signature (now parseFromData:error:)

Merge pull request #1764 from ctiller/so-the-standard-we-rely-on-is-actually-released-and-has-been-for-some-time

Advertise HTTP2 support via ALPN

Add testing of bad client behavior

Initial Doxygen configuration

Make -j on run_tests work as expected

Add TODO interop test case for CONTINUATIONS; clean up TODOs

Split C/C++ tests: we are running out of space in opt now

Add a check against potential failure to bring up client binary

Conflicts:
	tools/run_tests/run_tests.py

Added tracing for grpc_server_request_call

Standardize on |BIO_pending| and |BIO_wpending|.

Add simpler instructions for ObjC (using Homebrew)

It also clarifies the Cocoapods part for people new to Cocoapods, and links to the sample app for examples on how to use the generated library.

Updating our protobuf submodule to alpha3

OpenSSL offers 3 ways to express the same thing:

* BIO_ctrl_pending(BIO *)
* BIO_ctrl(BIO *, BIO_CTRL_PENDING, 0, NULL)
* BIO_pending(BIO *)

BoringSSL standardizes on the last of these.

Sync Python version to rest of project