[mr2735] Better differentiation from IsBinaryResistedSpell(...)

For Example AoE-Spells like Blizzard aren't BinaryResistenceSpell
+ some other Spells with Spellattribute SPELL_ATTR_EX6_EXPLICIT_NO_BINARY_RESIST like Frostbolt
"Frostbolt is no longer a Binary Spell." -> http://www.wowwiki.com/Binary_spell