Adding support for TLS connections for gRPC clients

This patch uses BoringSSL to negotiate TLS sessions under the hood.

Change-Id: I1495479ff33654f9cffe04d61f293c3e923b8aeb
diff --git a/protocols/grpc/ctl/BUILD b/protocols/grpc/ctl/BUILD
index 11f98c0..a467398 100644
--- a/protocols/grpc/ctl/BUILD
+++ b/protocols/grpc/ctl/BUILD
@@ -6,6 +6,7 @@
     "@io_grpc_grpc_java//protobuf-lite",
     "@com_google_protobuf//:protobuf_java",
     "@com_google_api_grpc_proto_google_common_protos//jar",
+    "@io_netty_netty_handler//jar",
 ]
 
 osgi_jar(