Adds release notes for 2.0.0 (#186) (#187)

Signed-off-by: Clay Downs <downsrob@amazon.com>
(cherry picked from commit ced0a6f)

Co-authored-by: Clay Downs <downsrob@amazon.com>

release-notes/opensearch.job-scheduler.release-notes-2.0.0.0.md

@@ -0,0 +1,21 @@
+## Version 2.0.0.0 2022-05-18
+
+Compatible with OpenSearch 2.0.0
+
+### Features
+* Enables locking on an arbitrary lockID ([164](https://github.com/opensearch-project/job-scheduler/pull/164))
+
+### Infrastructure
+* Fix qualifier to be added as version number matching with core ([152](https://github.com/opensearch-project/job-scheduler/pull/152))
+* Adding signoff option for version workflow PR ([156](https://github.com/opensearch-project/job-scheduler/pull/156))
+* Add default alpha1 to JS qualifier ([162](https://github.com/opensearch-project/job-scheduler/pull/162))
+* Remove hardcoding snapshot for JS in gradle ([163](https://github.com/opensearch-project/job-scheduler/pull/163))
+
+### Documentation
+* Updated issue templates from .github. ([165](https://github.com/opensearch-project/job-scheduler/pull/165))
+
+### Maintenance
+* Removes usage of mapping types ([155](https://github.com/opensearch-project/job-scheduler/pull/155))
+* Dropping support for jdk 14 ([168](https://github.com/opensearch-project/job-scheduler/pull/168))
+* Incremented version to 2.0-rc1.  ([169](https://github.com/opensearch-project/job-scheduler/pull/169))
+* Removes rc1 version qualifier  ([178](https://github.com/opensearch-project/job-scheduler/pull/178))