* add heart beat handler to jetty

* add heart beat handler to jetty

@lemon @ascrutae I change the proto file path for preparing 6.0, but didn't change .net namespace. But I think if you sync the protocol submodule, you still need some changes.

* Change version 

* #1202

1. Determine the log is enabled for the DEBUG level before printing message.
2. Make the columns initialize to be static attribute.
3. Topology build optimize: Cache query result to avoid repeating queries.

* #1202

Add elasticsearch batch process setting into application.yml.

* #1202

Fixed check style error.

* #1202

Use XContentFactory to build source to insert into elasticsearch.

* Add Zipkin receiver

Module class rename to ModuleDefine, Module is the JDK9 class. It is conflict with our Module class. (#1168)

* init test

* update

* agent-grpc-test

* part

* fix based on org.apache.skywalking.apm.agent.core.context.trace.AbstractTracingSpan.logs

* Fix Code Bug

* Add Test

* Fix Text

* add SegmentCounterTest

* fix based on org.apache.skywalking.apm.agent.core.context.trace.AbstractTracingSpan.logs

* Fix Code Bug

* Fix Doc

* Refactor the collector configuration initialization.

#1047

* 1. Add the performance collection point.
2. Report formatter.

#1032

* Add a new cache implementation by caffeine.

#1032

* Performance optimization:
Make all the loggers class variable to have the static modifier.

#1009

* 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.

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

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

2. Add column named service_name_keyword into service_name elastic search table by the type of keyword.

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

Use listener factory to create new instance when create SegmentParser instance. Because of the listener is stateful.