Printrbot Original Remix

I had extra parts laying around around upgrading my Simple, so I decided to redesign the original Printrbot. It not has endstops, uses GT2 belts, uses the Printrbot Delrin ACME nuts, uses the Makemendel extruder/hot end combo, has a Z rod stabilizer and handle, uses the Simple's 6.5 inch 8mm rods, the Simple's bed, and there are probably some other changes!

I got it all assembled, there are a few more things to do though. The X axis will be updated to use the smaller rods and the extruder mou