* Move submodule plugin.

* Always auto-submodule

* [maven-release-plugin] prepare release v6.1.0

* [maven-release-plugin] prepare for next development iteration

* Change keys location.

* [maven-release-plugin] prepare release v6.0.0-GA

* [maven-release-plugin] prepare for next development iteration

* Support overwrite tag

* Fix test case

* Update new protocol

* Support new protocol at agent side.

* Fix test case.

* Make backend supports new trace protocol

* Fix tests.

* Make all new services available in gRPC.

* Fix bugs.

* Finish new document for v2 trace protocol.

* Fix wrong version requirement of zk

* Fix trace query bug.

* Find a client side dictionary bug.

* Fix register bugs.

* Fix break doc links.

* Add some supports to sw6 header. Break many test cases because I turn sw3 default off. For sure, you could open in agent.conf.  FYI @peng-yongsheng @ascrutae

* Fix CI and make user cases still work under v1 header.

* Support BASE64 in v2 header and make entryOperationName and parentOperationName optional in ContextCarrier or ContextSnapshot

* Fix CI.

* @peng-yongsheng This is backend related, please pay attention.

* Fix the carrier item order is incorrect (#1903)

* 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 RuntimeContext cannot store anything when the trace is not create

* Add RuntimecontextSnapshot and remove debug info

* Change version 

Fix IPMC checks for releasing.

* [maven-release-plugin] prepare release apm-5.0.0-alpha

* [maven-release-plugin] prepare for next development iteration

Fix assmbly for mvn clean install -Papache-release and update version to SNAPSHOT for SNAPSHOT release.