Ring of Flames bug fix, remove focus time.

Fixed a bug that caused Ring of Flames to start casting, take mana and regs but not complete when cast by a player who otherwise couldn't cast a harmful spell on another on that screen. The spell now correctly checks if the player can cast the spell first before paying costs.

Also removed the focus time; while this is a 5th level spell and quite potent it's not really on the same level as the other short-focus spells (i.e. AmA, ET).