Lobby and map building update.

Changelog
+ Added player statistics
+ Added leaderboards for player statistics
+ Added information boards to help out new players
+ Added arena leaderboards
+ Added mutton, wolf eggs, iron golem eggs, more potions and arrows, and care packages to the shop

* Shop GUI changed to have separate menus for each type of item
* Shop item changed from gold ingot to emerald
* Player exp, levels, and inventory is now saved before teleporting to an arena and is returned to them upon teleport back to lobby
* Base gems per round was halved
* GUIs were spread out and lore was added where needed
* Creating spawns now won't return to the previous menu
* Many bug fixes
* Updated configs and data file structures to reflect changes