Add --keep, --min-atime and --min-mtime flags to aura -Bc

[AmmoniumX]

It would be great if aura had support for the same cleanup arguments that paccache -r does. This would allow users to schedule cleanup of package snapshots depending on their specific needs, e.g. number of snapshots or time since last modified.

Specifically, these paccache flags would be great:

-k, --keep <num>        keep "num" of each package in the cache (default: 3)
--min-atime <time>
--min-mtime <time>  keep packages with an atime/mtime that is not older than the time given, 
even if this means keeping more than specified through the '--keep' option. 
Accepts arguments according to 'info "Date input formats"', e.g. '30 days ago'

[fosskers]

Thanks, I'll consider these.