Fix TSAN failure in tcp_server (shown via qps_openloop_test)

Ruby garbage collection fixes

removed unused version of status_code_enum.h

Initialize variables in surface/call.c

Make running individual Python tests less painful

Change port_server.py to use port 32766

Expunge all references to zookeeper

Add http2 status code in error_message if it's not 200

Contributed cmake project files.

Removed invalid sentence from interop flag description

We'll need to fix coverage testing in the future anyway (see #6894).

Before this change, running Python tests individually required
building a tox environment via the run_tests script and then specifying
long environment variables to filter out just the test we wanted to run
(and then we wouldn't be able to get the output on interrupt, nor would
we have an easy way of determining the PID of the process for debugger
attachment). Now invoking the build_python.sh script creates a workable
python virtual environment that includes all necessary libraries and
tests (s.t. running a single test is now possible by just knowing the
module name). This does not change existing supported means of running
tests (e.g. through run_tests.py).

An additional way of running individual tests has been introduced.
Following invocation of `./tools/run_tests/build_python.sh` (or
run_tests.py), one may invoke

  ./$VENV/bin/python -m $TEST_MODULE_NAME

and acquire a single running process that *is* the test process (rather
than a parent of the process). $VENV is the virtual environment name
specified to `build_python.sh` (defaults to `py27`) and
$TEST_MODULE_NAME is what it says on the tin.

Moves all tests into a separate package. This does not change existing
supported means of running tests (e.g. through run_tests.py).

32767 is used by filenet-powsrm

Fix memory leak, fix error.c refcount reporting

Build objective-c examples as part of automatic tests

Add a maybe-temporary way for apps to clear the channel cache

fix for working with compressed data. Fixes #6746.

Use open-source defaults to propagate Python plugin configuration

Fix bug with override_server flag in run_interop_tests.py

Dont create errors redundently in chttp2_transport.c

implemented eventfd_check_availability

Fix Python server interop spec noncompliance

PHP: fix shutdown hang issue