The Belt of Holding!

Adds the Belt of Holding!
- It is a effectively a backpack for your belt!
- It has the same ability to create a singularity that the bag of
holding does.
- Like the Bag of Holding, it will disrupt teleports.
- Same tech cost of a Bag of Holding, but at a lower cost, as it is an
inferior item.

Sprite by MrSnapwalk.
Merge pull request #618 from GunHog/Holding_Belt

The Belt of Holding!