* Collector instrument agent.

* Make the agent.jar output to the /agent folder in collector package.

* Try to add metric annotation.

* Change the instrument ways.

* Reformat.

* Finish the agent codes. Wait for @peng-yongsheng 's metric requirements.

* Debug new instrument.

* Fix a detect bug.

* Finish the instrument

* Fix compile issue.

#1007

* Add client side token.

* Fix ci.

* Fix most codes of token auth at both sides.

* Add settings in config files.

* Make auth interceptor doesn't throw expcetion.

* Update AuthenticationSimpleChecker.java

* Update AuthenticationActivator.java

* Revert "Update AuthenticationActivator.java"

This reverts commit 0935f18fd6802ab84c12e0609c21ef753ff51be3.

* Merge branch 'feature/token-auth' of https://github.com/apache/incubator-skywalking into feature/token-auth

# Conflicts:
#	apm-collector/apm-collector-agent/agent-grpc/agent-grpc-provider/src/main/java/org/apache/skywalking/apm/collector/agent/grpc/provider/AuthenticationSimpleChecker.java

* Fix Auhentication token works incorrect (#1001)

* Fix Auhentication token works incorrect

* Change way to build GRPC Channel

* Response an empty header when auth fails.

#998

Fixed #999

* Fix link to proto files

* Fix proto path.

* Support setting override through system.properties and envs.

* Remove test case.

* Upload more dependencies.

* Add all UI licenses to license file.

* fix ui

* Update How-to-release.md

* Update How-to-release.md

Fix IPMC checks for releasing.

* Support direct server setting in agent.

* Fix format.

* Add direct_servers check (#981)

* 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.

* Proposal the code structure for table name prefix. Related to #932

* Fix style check.

* Keep ESDao table name in control.

* Finish all codes about ES namespace feature.

* fix #939

fix #939

* fixcheckstyle

* add npm install error tips.

tell people use taobao's npm source.

* Update How-to-build-CN.md

* Update docs for alpha release

* Delete a comma.

* Update How-to-build.md

* Add data-set licenses file

* Rename LICENSES-data-set to LICENSE-data-set

* Update LICENSE

* Remove fastclick from LICENSE

* Make the git submodule command to be a maven profile plugin. Let this command not execute by default install command.

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

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

* Product name is not correct

* Add more documents for release.

* Change profile id.

* Add CHANGES file in distribution file.

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

This reverts commit ac815019.

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

This reverts commit 095597c9.

* Add rat plugin to check dependency license and add license head into missing files.

* Fix docs.

* Exclude web ui config file.

* Next release guide.

* UI update.

* Update docs.

* Build source shell.

* Update docs and source release.

* remove .sha256 requirement.

* Update How-to-release.md

* Update How-to-release.md

* Update build doc.

* Update docs.

* Update How-to-release.md

* Update How-to-release.md

* Update docs for alpha release

* Delete a comma.

* Update How-to-build.md

* Add data-set licenses file

* Rename LICENSES-data-set to LICENSE-data-set

* Update LICENSE

* Remove fastclick from LICENSE

* Make the git submodule command to be a maven profile plugin. Let this command not execute by default install command.

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

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

* Product name is not correct

* Add more documents for release.

* Change profile id.

* Add CHANGES file in distribution file.

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

This reverts commit ac815019.

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

This reverts commit 095597c9.

* Add rat plugin to check dependency license and add license head into missing files.

* Fix docs.

* Exclude web ui config file.

* Next release guide.

* UI update.

* Update docs.

* Build source shell.

* Support zk namespace, #935

* Revert default changes.

* Update README.md

* Update README_ZH.md

* Update README.md

* Update README_ZH.md

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

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

* Add more dependency licenses.

* Change the asm component’s license.

* Update CHANGELOG.md

* Update Deploy-backend-in-standalone-mode.md

* Add license file.

* Update license and notice files.

* Add licenses of dependencies.

* Add license.

* Create style check module.

* Add scm, licenses, mailing lists into root pom.

* Add jacoco and coveralls maven plugin into check style module’s pom.

* Update README.md

* Update README_ZH.md