* update 5.x grpc version form 1.10 to 1.14 and Solve the resulting guava and log4j version conflicts
* Specify guava version 20.0
* update parrent pom guava version
* Finish the prototype of TLS of gRPC between agent and server.
* Fix for rat check.
* Update GRPCChannelManager.java
* Update AgentModuleGRPCProvider.java
* Upgrade netty version (#971)
* Make sure end user can't start gRPC server with and without SSL in the same port.