* get_peer: fix todo
* add documentation for server registered call function
* test roundtrip conversion of larger bytestrings (32 mb)
* Add channel args interface: currently supports user agents and compression.
* fix build failure after stack clean
* fix testWrongEndpoint
* test that unregistered requests are ignored by request_registered_call
* handler returns status code, drop Grpc prefix from status codes
* begin module with LowLevel tests of Op stuff, cancel functions, refactor Ops a little.
* refactor op tests, add server-side cancellation test
* add cancel function for unregistered calls, move some unregistered stuff
* remove unnecessary threadDelay
* update test description
* fix init metadata api for registered server calls
* pass call into handler for cancelling, add cancel test
* initial echo client/server examples
* registered and unregistered versions of the example client
* ignore pyc files
* cpp echo code, flag to build examples
* threaded server example