Fury of Nature spell

Created a new Faren 6 spell that will hopefully solve quite a few
problems for the magic attack school. "Fury of Nature" is a simple self-only
PE that cannot be purged and cannot fizzle.

It has a flat effect tradeoff: it prevents fizzles for Faren attack
spells and adds 2 damage, at the cost of 2 extra mana per cast. Attack
spells already lose damage if their spellpower is weak (down to half),
and mana costs go up as well, so this spell works very will with the
existing inherent balances. It just lets Faren mages do *something*
rather than *nothing* the moment an Anti-magic Aura goes up or a Dement
hits them.