Moved the license checker config into the parent pom, and overrede
the license dir/target-to-check in distributions/pom.
Disabled the license checker explicitly for projects which run integration
tests but have no licenses dir:
* core
* distribution
* qa
* plugins/delete-by-query
* plugins/mapper-size
* plugins/site-example
Closes#12752Closes#12754
This is one of our esoteric metadata mappers so I think we should distribute
it in a plugin rather than in elasticsearch core.
This introduces one limitation: the value of the `_size` parameter is not
retrievable for documents that are only in the transaction log.
Clinton Gormley
Adrien Grand