signing-party: Fix deps and include all tools

Additional tools:
- gpg-key2latex
- gpgdir
- gpgwrap

This module is really hacky and the dependencies are very messy... :o

However I tried my best at testing all 19 individual tools and they
should (hopefully) all work now (apart from sendmail which can be
provided by multiple packages) :)

The code is very redundant (sorry) but imho it's easier to read and
maintain it that way.

TODO: There are some additional manual pages that could be included (I'm
too exhausted for that atm...). And there might be a lot of stuff that
could be improved in the future.