Increase timeout for build step jobs to 10 mins

Add Node Auth plugin code

Reduce parallelism for windows build

Fix #2275 (Make sure PHP example can be run with Apache)

Node package cleanup

Node single install step

build.json reappeared

release-0_11 -> master integration

Fix connectivity tests under Windows

More robust port_server version checking

Enable `pip` caching

Fix broken udp_server_test, by adding exec_ctx to read_cb

"gRPC in 3 minutes" for Python

Node interop custom_metadata

Add verbosity to Python `run_tests.py` output.

Normal constants, like most other things, are cleaned up during
RSHUTDOWN.
We need to explicitly mark them as persistent using CONST_PERSISTENT

unref slice before cancel

Type conversion fixes to make GCC 5.2.0 happy

Fix thread stuck problem on Mac

Add auth interop test support to run_interop_tests.py

Add ruby server to run_interop_tests.py