Sync to latest ET open and introduce inappropriate as a classification
to replace something some find inappropriate.
(cherry picked from commit f037f6f4ff)
Install classification.config and reference.config to $datadir,
where they can be updated on every upgrade.
This required moving them into a sub-directory for autotools
to do its thing.
Redmine issue:
https://redmine.openinfosecfoundation.org/issues/3209