Charms : Add cleanup toggle to avoid conflicts when merging services into same unit.

[davidfischer-ch]

... Or some packages required by services that are already running on the unit will be removed (configuration deleted) and maybe not re-installed !

DIY

sudo apt-get install glusterfs-server sudo apt-get remove glusterfs-client

This will remove glusterfs-server !

Tasks

• [x] Add toggle to config.yaml of all charms
• [x] Update *Hooks.py according to use this toggle