Move /var/ideascube to /var/lib/ideascube

[bochecha]

Eventually, the ideascube package will start installing its stuff in /var/lib/ideascube instead of the current /var/ideascube.

This is going to have a pretty big impact, so we need to plan it carefully, both for new machines and upgrades.

Let's use this ticket to start figuring out all that needs to be changed for this.