If a deployer installs AIDE the first time they apply the role
without initializing AIDE and they want to initialize it later,
the handler that does the initialization never fires.
This patch does a few things:
- Ensures AIDE initialization if the initialize_aide bool is True
- Doesn't intialize the AIDE db if it already exists
- Moves the new db into place on Red Hat systems
- Moves the AIDE tasks into its own file with tags
- Prevents AIDE from trawling through /var
Manual backport of two reviews:
* https://review.openstack.org/#/c/359554/
* https://review.openstack.org/#/c/361460/
Closes-bug: 1616281
Depends-on: I60aa62ff688d32c14031773d35af29b3cf6b6fd6
Change-Id: I170eb3898b4336333b1fbe663ec4f069823898e0