* add oal excludes and includes to support tags
Co-authored-by: 吴晟 Wu Sheng <wu.sheng@foxmail.com>

* Support new percentile func with new alarm and exporter for this new func.

* Fix e2e and OAL script

* Fix wrong column.

* Fix percentile bug and oal engine bug.

* Update query protocol and add percentile test case

* Support new query

* Adopt GraphQL requirement

* Fix wrong type cast.

* Fix query in H2 and ES.

* Fix docs and comments.

* Fix an e2e compile issue

* Fix javadoc issue and e2e test issue.

* Change CPM to Apdex in TTL test.

* Fix OAL for TTL e2e

* Add metrics query for service percentile.

* Fix OAL engine bug. Method deserialize is not working when more than two field types are IntKeyLongValueHashMap

* Support multiple IntKeyLongValueHashMap fields in remote. About serialize/deserialize methods.

* Fix graphql statement error in e2e.

* Fix serialize not working and add generated serialize/deserialize of percentile into test cases.

* Fix test case format

* Remove generated code test.

* Fix failed e2e test

* Use avg resp time to apdex in the TTL test.

* ADD multiple linear metrics check for endpoint in e2e cluster.

* Support `-` to represent no threshold and doc of alarm about this.

* Move break to right place.

* Fix wrong break(s)

* Fix break and add a test case for multiple values alarm.

* Fix format.

* Add more doc for this new feature and GraphQL query protocol.
Co-authored-by: NJared Tan <jian.tan@daocloud.io>
Co-authored-by: Nkezhenxu94 <kezhenxu94@163.com>

* Change OAL generator tool to runtime.

Step 1. change project structure. API links and maven pom.

* Part of metrics class generation

* Metrcis class generated.

* Set up the basic structure of new OAL engine.

* Finish metrics generation.

* Support dispatcher generation.

* Format codes.

* Generate dispatcher all methods.

* Implement disable in hardcode.

* Clear up

* Fix compile startup.

* Update license and document of new OAL engine.

* Fix rat.

* Disable class output in default

* Copy from @kezhenxu94 's test PR, https://github.com/apache/skywalking/pull/3110

* Wait for the mount command to finish

* Rename metric to metrics.

* Fixed test case execute failure issues.

* Try to make disable work.

* Make disable works.

* Add disable document.

* Change oal doc.

* Remove typo

* Remove document WIP tag.

* Fix few words.

* no message

* Adjust contribution guides.

Init branch 6.0 for our next big iteration. Change root readme. Format field document in table.  Remove Chinese documents.