Tomes of Experience

Adds six different tomes that can store experience points - and give them back to the player.  The tomes are craftable in-game and have configurable attributes. They follow the following hierarchy: - Tome of Minor Experience - Tome of Lesser Experience - Tome of Experience - Tome of Greater Experience - Tome of Superior Experience - Tome of Major Experience Tomes are intended to be used while being held in the player's main hand. - Sneak (Shift) + Use (Right-click) to transfer experience points to the tome the player is holding - Use (Right-click) to transfer experience points from a tome to the player holding it Refer to the [wiki](https://github.com/hanskroner/tomes-of-experience/wiki) for information on the different tomes, their crafting recipes, and how to adjust their configuration.