* Codebase for zipkin span persistence.

* Fix missing fields in storage.

* Miss the latency field.

* Finish some tests.

* Fix wrong latency.

* Finish doc and reset application.yml

* Make the description more clear.

* Change some codes to make zipkin receiver works, not done yet.

* @adriancole Zipkin receiver is coming back again.

* Fix document and fix for Zipkin receiver.

* Fix some bugs.

* Fix register bug.

* Fix transfer bug for new backend core.

* H2 storage code skeleton.

* Add batch dao for H2.

* Fix wrong refactor.

* Add codes of other dao. No metric dao, wait for @peng-yongsheng new PR.

* Change license of distribution

* Add topology query in H2.

* Add more daos.

* Add some daos.

* Commit all H2 daos. Wait @peng-yongsheng to submit new IAggregationQueryDAO interface.

* Fix some CIs

* Fix wrong refactor, which causes h2 plugin failure.

* Fix all codes of H2 storage. :) and CI should pass. No test.

* Fix CI and typo

* Fix connection closed.

* Fix register bug

* no message

* Fixed service inventory register bug.

* Fix a compile issue.

* Sync change

* Reset es as default storage.

* Fix rat

* Fix H2 compile issue.

* Fix bugs for H2 storage.

* Fix bug in mesh.

* 1. Fix Thermodynamic query bug
2. Fix service inventory query bug
3. Fix missing traceid in trace query bug

* Fix query bug.

* Submit reverse caused by prev PR.

* Fix duplicate spans.

* Use H2 as default storage implementor.

* Fix bug in topology query.

* Fix CI

* Fix rat

* Fix two query in H2 storage.

* Fix H2 query

* Make release running in H2 mode and develop mode running is ES mode in default