Bitminers (Miner Shelf, Power Sources, Cables, Animations & Custom Models)

UPDATE

1. Bitminers will no longer turn on when you connect a power combiner/power source that hasn't generated any watts.
2. Only once some watts are generated, then the bitmining shelf can be turned on.
3. Bitminers now automatically shut down once they hit 0 watts.
4. This can only happen if you have a power combiner connected with no power sources.
5. Removed redundant code.
6. Fixed power cables sometimes connecting to the same slot on power combiner.
7. They will now always find an empty slot and connect to that.