* docs(kbn-20086): steps to get kibana running after upgrading to 6.3.0 with an old x-pack installation.
* docs(kbn-20086): updated text for docs related with 6.3.0 upgrade.
* docs(kbn-20086): change wording from docs text.
* [DOCS] 6.3 Release Notes
* [DOCS] Incorporated review comments
* [DOC] Updated note about regression because it also affects pipeline creation
* [DOCS] Minor updates to release notes