Merge branch 'master' of github.com:grpc/grpc into core_codegen_be_public

BUILD

Makefile

README.md

binding.gyp

build.yaml

config.m4

doc/connectivity-semantics-and-api.md

examples/cpp/helloworld/Makefile

examples/node/static_codegen/helloworld_grpc_pb.js

examples/node/static_codegen/helloworld_pb.js

...es/node/static_codegen/route_guide/route_guide_grpc_pb.js

examples/node/static_codegen/route_guide/route_guide_pb.js

examples/ruby/lib/helloworld_services.rb

examples/ruby/lib/route_guide_services.rb

gRPC.podspec

grpc.def

grpc.gemspec

include/grpc++/impl/codegen/async_stream.h

include/grpc++/impl/codegen/async_unary_call.h

include/grpc++/impl/codegen/call.h