Opendistro Release 1.9.0 (opendistro-for-elasticsearch#532)

* prepare odfe 1.9

* Fix all ES 7.8 compile and build errors

* Revert changes as Lombok is working now

* Update CustomExternalTestCluster.java

* Fix license headers check

* Use splitFieldsByMetadata to separate fields when calling SearchHit constructor

* More fixes for ODFE 1.9

* Remove todo statement

* Add ODFE 1.9.0 release notes

Update Opendistro 1.8 releaes notes (opendistro-for-elasticsearch#471)

* Update Opendistro 1.8 releaes notes

* add opendistro-for-elasticsearch#462

* move release notes to release-notes folder

Opendistro Release 1.7.0 (opendistro-for-elasticsearch#459)

Update release doc for v1.6.0.0 and fix issue in IT test with externa…

…l cluster (opendistro-for-elasticsearch#393)

* fix failure in IT test with external cluster
* update release doc

OD 1.4 Release (opendistro-for-elasticsearch#314)

Preparing branch for OD 1.4 release

OD 1.4 Release (opendistro-for-elasticsearch#314) (opendistro-for-ela…

…sticsearch#319)

Merging 1.4 release changes into master

Support CASE statement in one more grammer (opendistro-for-elasticsea…

…rch#262)

* Reassign condition expressions of the items in case express

* Added UT and IT

* Fixed the JDBC formatter for the case statement

* Added IT to test JDBC formatter for the case when statement

* Updated the release notes

Updating release notes and documentation/download links (opendistro-f…

…or-elasticsearch#137)

*Issue*: opendistro-for-elasticsearch#134

*Description of changes*: Updated release notes and fixed the broken links.

Fixed unit test failure that was identified on a Jenkins: date format…

… needs to be in UTC for proper comparison (opendistro-for-elasticsearch#130)

Updating release notes for 1.1.0 release (opendistro-for-elasticsearc…

…h#94)