Split garbd into separate package.
This will make it easier to install the package, as the install
will directly drop the init file in the correct place and
activate the arbitrator (and removal will de-activate it).
Rename package garbd to galera-arbitator for clarity in package listings.
Also clean up many minor issues spotted by Lintian '-EvIL +pedantic'
Skip extra license files as they are already covered in the d/copyright file.
This fixes the Lintian warning https://lintian.debian.org/tags/extra-license-file.html
Created manpage for garbd to satisfy Debian policy
Drop surplus homepage