Remove individual class licensing
Scoreboard now tracks how many players from each team are in the hill.
Start adding class data to both per-arena stats and per-player stats
Actually collect player class data.
Add getter to PlayerStats for class-data configuration section in order
to find the most commonly used class for the arena of the player.
Fix bug where non-conventional helmets, such as colored wool, would revert back to their default type (durability of 0) upon a player being damaged.