Improve shop jewelry crafting

This is mostly to add more uses for gems/gold, especially the unique gems.

- No longer requires a blank ring/amulet but doesn't keep any properties on the one given

- Cost, item level, and item base are based off the material tier of the components for rings and a flat 1000 cost for the Limmir amulet

- 20% of the time the ring generates as a randart

- Now creates a fake ego for the imbue so it plays nice with item modification stuff