Merge github.com:grpc/grpc into new_transport_op

BUILD

CMakeLists.txt

INSTALL.md

Makefile

binding.gyp

build.yaml

config.m4

gRPC-Core.podspec

grpc.gemspec

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

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

include/grpc/impl/codegen/grpc_types.h

package.xml

src/core/lib/channel/http_server_filter.c

src/core/lib/channel/max_age_filter.c

src/core/lib/channel/max_age_filter.h

src/core/lib/surface/init.c

src/cpp/common/completion_queue_cc.cc

src/cpp/server/server_context.cc

src/objective-c/tests/build_example_test.sh