Bug#586434: Let's clean the apt cache

[Frans Pop <elendil@planet.nl>]

On Sunday 20 June 2010, Frans Pop wrote:
> Any disk space savings are IMO illusionary as the cache will fill up
> again anyway during later updates and any system that does not have
> sufficient disk space to hold a decent package cache will also have
> serious problems during later stable updates.

I mainly mean upgrades from one stable release to the next (e.g. lenny -> 
squeeze). Point releases and individual security updates are much smaller 
and thus less of a problem.