Merge pull request #6924 from dgquintas/grpclb_v0

BUILD

CMakeLists.txt

Makefile

binding.gyp

build.yaml

config.m4

gRPC-Core.podspec

grpc.gemspec

package.xml

src/core/ext/client_config/lb_policy.h

src/core/ext/lb_policy/grpclb/grpclb.c

src/core/ext/lb_policy/grpclb/grpclb.h

src/core/ext/lb_policy/grpclb/load_balancer_api.c

src/core/ext/lb_policy/grpclb/load_balancer_api.h

src/core/plugin_registry/grpc_plugin_registry.c

src/core/plugin_registry/grpc_unsecure_plugin_registry.c

src/python/grpcio/grpc_core_dependencies.py

test/core/end2end/cq_verifier.c

test/core/end2end/cq_verifier.h

test/core/nanopb/fuzzer_response.c