Re-Implement Old Berserker Weapons

I suggest the discontinued Berserker character's weapons be added as a weapon to be purchased in the shop. This would add diversity to the combat system, as well as a bit of nostalgia for some of the older players.

A quick overview:

- Two axes

- No shield (no blocking)

- Whirlwind attack (special ability)

- Faster attack speed, lower damage per hit

The wielder should not have a faster running speed, nor any of the other old unbalanced Berserker attacks.