* Lock oracle and resin plugins version.
* Move resin and oracle plugin to openskywalking
* Restore submodule active.
* Add another submodule active command.
* Remove the wrong test cases in release and fix some doc issues.
* [maven-release-plugin] prepare release v6.0.0-alpha
* [maven-release-plugin] prepare for next development iteration
* Fix some doc
* Fix mesh receiver doesn't update heartbeat.
* Fix bug of mesh heartbeat and rest receiver.
* Fix issue: opencensus is included in agent without shade. @tuohai666
* 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.