New poudriere module for FreeBSD users.

Not sure if there's any demand for this, but this is a functional poudriere module that I'm using on a FreeBSD 9.1 system.  Frankly I don't have too much experience with poudriere other than to simply 'make it work', so I'm hoping that there are other users out there who can help test and provide feedback.  

If you're not familiar with poudriere, the tl;dr is that it's a system you can use to build packages.  Since FreeBSD's official binary package management is still in limbo, users are hosting their own packagesites and are using tools such as poudriere to build them up.