* Revert reset feature.

* Set default dist alarm settings and make dist package setting files right.

* Support empty list.

* Manually trigger agent registration and write registration status to file

* Delete unused variables

* Code optimization, encapsulating some methods

* add clear DataCarrier function

* revert SkyWalkingAgent

* Optimize code and logic, including updating applicatin_id in unRegisterOperationNames

* Server end metadata loss notification

* Server end metadata loss notification

* fix file stream close and other problem

* revert to old

* fix some bug
Signed-off-by: NLiu-XinYuan <879928098@qq.com>

* fix some bugs in agent reset

* add close inputStream and fileChannel and fix some bug

* fixed some bugs

Remove collector.servers and collector.direct_servers, and add collector.backend_service setting. cc @ascrutae

* Provide document for TLS

* Provide direct uplink doc.

* Add namespace document.

* Provide token auth doc.

* Provide setting override document.

* Fix two typo.

* Fix more typos.

* 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.

Fix IPMC checks for releasing.

* Support direct server setting in agent.

* Fix format.

* Add direct_servers check (#981)