Makes Supply Pack datums no longer garbage collect. Prevents them from making artifacts like mulebot #3. Fixes issue #137.

Moves the supply shuttle controller to the controller folder and adds its creation to the new proc of the master controller.
Also, makes the supply shuttle make supply packs on new instead process.
Merge branch 'master' of https://github.com/tgstation/-tg-station into Supplypacks
fixes a error I made when merging.
Merge pull request #1335 from KazeEspada/supplypacks

Fixes issue #137