[csw-buildfarm] Cleaning the buildfarm from packages no longer in the catalog

[Maciej (Matchek) Bliziński]

Hello buildfarm admins,

There is a subset of packages which are removed from the catalog but
still installed on the buildfarm. I'm thinking we should remove these,
or even better write a script that does it and run it regularly. Maybe
it could become one of the "do*" scripts on the ncsw zone?

Thoughts?

Maciej