* [maven-release-plugin] prepare release v8.4.0

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

* [maven-release-plugin] prepare release v8.3.0

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

* Update elasticsearch client 7.0.0 to elasticsearch client 7.5.0.
* Update CHANGES.md and LICENSE.

* [maven-release-plugin] prepare release v8.2.0

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

* [maven-release-plugin] prepare release v8.1.0

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

* [maven-release-plugin] prepare release v8.0.0

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

* Remove all shardingsphere cases.

* [maven-release-plugin] prepare release v7.0.0

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

Motivation:

Review code styles with some bots automatically.

Modifications:

Set up ReviewDog in GitHub Action to review code style.

Add more check rules to checkstyle plugin.

Result:

Obvious code styles can be reviewed and commented automatically.

* [maven-release-plugin] prepare release v6.6.0

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

* [Feature] Officially support ElasticSearch 7 as backend storage

* Extract bootstrap module to be shared by multiple starters

* Add missing configuration file and distinguish different version in test

* Update known-oap-backend-dependencies-es7.txt

Update the dependency lib

* Fix missing adaptation to ElasticSearch 7

* Rename ElasticSearch 7 specific class with Es7 infix

* Fix miss-adapted ElasticSearch DAO API

* Add ES7 specific configuration and polish documentations

* Polish documentations

* Polish documentations

* gateway-testcase

* provides a jvm-container

* Add e2e cluster tests

* [maven-release-plugin] prepare release v6.2.0

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

* 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.

* Make scope meta configurable.

* Fix test cases in ci.

* Change step 1

* Refactor step 2

* Other compile issue done. Prepare the generator changes.

* Revert some wrong changes to Istio receiver.

* Step 3, make compile pass.

* Try to make CI passed.

* Add a check.

* Fix generated code style

* Provide new and extendable dispatcher generator tool

* Fix startup.

* Can't guarantee the dispatchers are always existing. Put explicit comments at there to avoid confusion, since this is different with old version.

* Fix a H2 query for endpoint search.

* Fix a wrong mysql alarm query.

* Provide new document and `generate-tool-grammer` module.

* Add missing last section of document.

* Fix typo

* Relocate the @ScopeDeclaration annotation, make it more sense. Also remove the useless @SourceType annotation. And adjust document for these changes

* ScopeDeclaration can be used once for each class only, now.

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

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

* Move oal tool back into main repo, and fix compile issue.

* Fix two bugs.

* Remove all generated codes.

* Make all oal generated codes out of source control.

* Make mvn compile and package work.

* Fix test cases.

* Make compile right and provide new documents.

* Remove an unnecessary tokens file.

* Change some codes to make zipkin receiver works, not done yet.

* @adriancole Zipkin receiver is coming back again.

* Fix document and fix for Zipkin receiver.

* Fix some bugs.

* Fix register bug.

* Fix transfer bug for new backend core.

* 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

* Receiver, aggregate, server finished.

* Cluster module implementation finished.

* Add Zipkin receiver

#1009

* [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.