tor: additional optional deps

An additional optional dep for Tor.

Also removes the example file, as upstream regenerate it periodically and currently we don’t seem to respect that regeneration and leave outdated sample files in etc.

Adds a set of caveats about the ` torrc ` file, similar to the ones we have for ` clamav ` and others.
So the behaviour after `touch` is expected. I think this is fine as-is, honestly.