Merge pull request #5582 from devhell/profanity.

This add profanity and dependencies and a few cleanups from me for the
profanity package expression.

Thanks to @devhell and apologies for pestering him with my nitpicking.

* Commit summary:
  profanity: Add option for autoAwaySupport.
  profanity: Clean up package expression file.
  profanity: Add libnotifySupport config option
  all-packages: Add libnotify option to profanity
  profanity: Add "platforms" meta information
  profanity: Add libXScrnSaver and libX11 buildInputs
  libstrophe: Add "platforms" meta information
  libstrophe: Fix typo
  profanity: Add profanity, a ncurses XMPP client
  libstrophe: Add new package