Add extra packages for Stratum 0 and 1 on debian

[bedroge]

I am running into an issue with setting up a Stratum 1 on Ubuntu systems, because Squid doesn't get installed:

TASK [galaxyproject.cvmfs : Configure squid] ***********************************************************************************************************
fatal: [127.0.0.1]: FAILED! => {"changed": false, "checksum": "653ddf9c797f0fc5f68de2e22e4039b9768e531e", "msg": "Destination directory /etc/squid does not exist"}

Squid is listed in the Redhat package list as a dependency for the Stratum 1, but it's not in the Debian list. Could this be added?

[bedroge]

And I got a similar issue due to a missing libapache2-mod-wsgi, so I've added that one as well.

[bedroge]

And another similar issue for the stratum 0, for which the cvmfs client package was missing.