Mana Focus change

Mana Focus now gives attack spells an absolute value, which means they
will ignore resists and weaknesses. This will help Faren mages fight
against extremely buffed targets, but it won't allow them to capitalize
on gear weaknesses at the same time.

Mana Focus now has an up to 75% chance to resist focus disruption based
on spellpower. In practice, this will allow a Faren mage to use items,
run, and cast non-attack spells in a limited manner without losing
focus. The more actions a mage takes, the greater chance they'll lose
their mana focus.