Merge the existing "Gordon" code into "Pulls" so the two projects can be coalesced

See also the discussion on #42.

The only sticky point in the whole merge was trying to figure out what "deps/bender/bender" was, and it was a failed git submodule (committed the metadata without the .gitmodules).  I opted to just remove it instead of trying to resolve it, because it appeared to be referencing an outdated commit besides.

But!  That brings up nicely the other issue.  Do we need to bring in the current "Bender" code too?  Or do we leave that alone and start from scratch on a new IRC implementation when we're ready to transition to having an actual IRC bot? (my preferred option; this would obviously wait until the normal CLI tooling matures to the point where a bot makes sense, especially and including a GitHub commenting bot)