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

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

* Modify MySQLDAO and H2DAO

* Fix service instance ID build bug.

* Add instance ids into the relation metrics.

* Add Java agent plugin for Jdk Threading

* Fix expected data according to changes in master

* Update agent.config

* Fix failed plugin test

* support min function.

* fix logical bug and update test case.

* the same here.

* Remove the local span and exit span register mechanism in Java agent scenario.

* Fix config, plugin, and document, as exit span is not required register anymore.

* Try to fix the test case expected data due to no register for exit span.

* Fix toolkit case.

* Remove exit span from plugin test framework document.

* Update protocol, FAQ, and CHANGELOG documents to highlight this change.

* Fix NPE when no entry span in the whole segment. Set endpoint to null in segment entity.

* Fix the snapshot and add inexistence operation name id.

* Fix several async cases.

* Fix undertow test case.

* Fix wrong error log name.

* Keep name consistent with 6.x concepts.

* Try to fix 3 async scenarios.

* Fix okhttp case.

* Fix Spring Async case.

* Fix another NPE

* Fix NPE when first span has no endpoint id when it is local or exit span.

* Still fill first operation name when no endpoint id.

* dispatcher

* getServiceInstanceTopology implementation

* CacheUpdateTimer

* fix compilation failure

* fix compilation failure

* fix esDao

* Update dao list

* dispatcher

* getServiceInstanceTopology implementation

* CacheUpdateTimer

* fix compilation failure

* fix compilation failure

* fix esDao

* Update dao list

* test e2e

* add official_analysis.oal & update getServiceInstanceTopology

* test instance topo for single service

* fix gql

* fix verifyServiceInstances

* verifyServiceInstanceTopo

* fix verifyServiceInstanceTopo

* fix ServiceInstanceInventory#name

* fix ServiceInstanceInventory#name

* e2e test

* fix action

* fix provider port

* fix Instance Node Type

* re run

* fix expected-data

* add e2e mysql

* set @test timeout

* fix ci

* increase timeout

* re check

* test ttl es7

* test ttl

* fix action

* merge group

* test ttl es7

* replace official_analysis.oal

* replace official_analysis.oal

* comments

* add TODO

* add TODO

* fix filed name

* Update pom.xml

Exclude "service-apdex-threshold.yml" from jar

* Add service-apdex-threshold.yml to the config folder of release jar

* Add apdex function to OAL

* Add empty line

* Setup config watcher

* Add identifier type to function parameter

* Add config test

* Update score algorithm

* Replace responseCode with status

* Add comments about apdex score algorithm

* Add docs

* Add e2e test case

* Update test case

* Fix disptch class generating error

* Update value name of apdex metric

* Tuning threshold

* Fix single tolerated point bug

* [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

* Sort the segment fragments

* Add comment.

* Remove unnecessary box codes.

* plugin code

* NPE FIX

* Add componentId for apache servicecomb.

* Edit according to comment

* add servicecomb

* Edit according to comment

* fix

* set no statement.

* update sql.

* update statement.

* revert threshold.

* Update joda lib to fix UTC 13/14 bug

* Change the dependencies file.

* Refactor DataCarrier, support ArrayBlockingQueueBuffer as the implementation for blocking queue buffer.

* Fix style issue.

* Remove import.

* Remove uesless codes.

* fix component-libraries.yml miss component:rest-high-level-client

* Update component-libraries.yml

Add mapping.

* Add elasticsearch 6.x plugin & elasticsearch 6.x test scenario

* [maven-release-plugin] prepare release v6.5.0

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

* Update EtcdCoordinator.java

when EtcdCoordinator cannot connect to etcd cluster for a long time, 
the information registered in etcd will expire and refresh() function will not work.

* fix elasticsearch query data window size too large error.

* make query max window size configurable.

* Add register persistent worker latency metrics  #3671

* remove never thrown exception on Time#close()
add panel to mesh-mode-grafana.json

* remove never thrown exception on Time#close()
add panel to mesh-mode-grafana.json

* add plugin netty-socketio https://github.com/mrniko/netty-socketio

* delete create exit span interceptor.

* delete create exit span interceptor testcase.

* delete create exit span interceptor testcase.

* add constructor test unit

* change bind on random port in test case

* reverse upstream master whitespace

* resolve build_id param

* delete health check segment test case

* add ContextManager.isActive check before use activeSpan invoke

* remove unnecessary code and blank line

* Makes the scope of alarm information more semantic.

* update md.

* update md.

* add ruleName in AlarmMsg.

* update md.

* update test case.

* fix coveralls.

* fix coveralls.

* fix ci.