PrettySimpleShop

This build should be mostly compatible with 1.13 and fully compatible with 1.12.2.

• Gracefully disables transaction confirmations if the included BookUtil is out of date. (i.e., 1.13 servers at the moment won't have the transaction confirmation feature until a future release).
• Fixes displayed items not being removed for doublechest shops that cross a chunk border.
• Some other typos and stuff I made in non-released versions (been working off and on this for a few months despite no releases, primarily fixing little issues.)