initial stab at packaging using ship_it

So this is not yet ready to merge.  The good news is that I'm able to make an RPM with this changeset which seems to install properly.  The bad news is that now that we've changed Sideboard to use a single virtualenv, we are no longer able to bundle plugin Python dependencies with those plugins as easily :/

So basically, we need to be able to have packages somehow insert their dependencies into Sideboard's virtualenv on install.  We do NOT want to pull down from the internet when we do this.  Perhaps the solution is to include the packages and then do the equivalent of ``python setup.py install`` on each of them to make sure they're installed, but I'll need to give that some thought.
I had to rewrite a lot of this from what we've been using in the past, but it's finally doing a lot of things right that we haven't done in the past, such as
* not defining a bunch of varuiables we don't even use (though now that I say this I realize that we're not using the ``DESC`` variable, which I'll probably remove)
* dropping to the ``sideboard`` user instead of defining that user but then just running it as root
* not relying on a lot of platform specific functions; although I haven't tested it I would expect this script to work properly for both our .deb and .rpm packages