* Update powered-by.md

* Update powered-by.md

Adjust order. And highlight order.

* add User Case

* add User Case

* Provide consul cluster plugin.

* Change log and application config file.

* Add consul's config item into the docker's application.yml.

* Fixed bug.

* Add consul description into  readme.

* Add okhttp component license.

* Support webflux and spring mvc 5 plugin

* Change instrumentation

* Change instrumentation

* fix check style

* Add support 2.1.x instrumentation

* 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.

2. Zookeeper implementation of the cluster module using name space to support using same zookeeper cluster by different OAP clusters.

* Support alarm in service instance and endpoint.

* Fix alarm default settings and document.

* Fix wrong default setting

* Make service instance and endpoint scopes available in alarm core.

* Fix alarm bug.

* Update document and user wall.

* Change format.

* user wall updated.

* Fix typo

* Correct namespace description

* Support sampling trace at server side and keep metric right.

* Add a trace sampling document

* Fix wrong default value.

* Fix document issue.

* Fix assemble issue.

* Fix wrong settings and doc.

* add TiDB configuration description.

* add tested mysql client driver version

Also fixed several bugs in this merge.

Notice of the system time setting.

* feat:Active System.env Config In Both Collector And agent.config.
1、moving related codes into apm-util module.
2、update Setting-override.md about how to use.

* resolve docs.

* typo

* finish test case.

* Update README.md

* Update powered-by.md

Guazi.com and Maodou.com are using Apache SkyWalking for research and production,
and providing commercial products including Apache SkyWalking.

* Update powered-by.md

Fix order.

* support set config from system.envs.

* 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.

* 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.

Fix typo

* ZooKeeper Version Compatibility

* Update backend-cluster.md

Reorganize words. cc @peng-yongsheng

* Update application.yml

* Update application.yml

* Support for overriding config with agent options

* Test the separator of options

* support quotes in agent options

* revert imports change

* add more tests

* clear properties after each test

* add document

* fix code style

* Add Rocketbot ui

* update set-up

* Update powered-by.md

www.mobanker.com user skywalking

* Update powered-by.md

Change order.

* Update powered-by.md

* 拉勾网使用skywalking进行调用链路监控

* Update powered-by.md

Change order only.

* 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

* Update README.md

* Update Screenshots.md

* Update Screenshots.md

* Update Screenshots.md

add user case Yonghui Superstores

* Update powered-by.md

添加使用公司

* Update powered-by.md

Format order.

grammar fix

* Avoid service inventory object concurrency situation.

* Fix concurrency for minute persistence and others

* Fix document todo.

* Update license. Fix package with dirty agent plugin jar files.

* Fixed not combine error in persistence register worker.

* Update submodule skywalking-ui

* Add kubernetes and istio setup documents

* Remove kubernetes scripts