Cleanup Afflatus Misery / Banish Magic.lua Path

This was done at @teschnei's request, as he doesnt want any sepll that doesn't get a bonus from Afflatus Misery to be on the same codepath.

So what I had to do to achieve this, is split Banish spells into their own codepath, doDivineBanishNuke() - this is necessary because the Afflatus Misery only applies bonuses to Banish spells, NOT Holy

I then placed the call to HandleAfflatusMisery in the doDivineBanishNuke code path, and then was able to remove the checks for divine skill and eligible spells

Let me know if this is sufficient for you. This way the Banish formula calculation is at least centralized instead of copy/pasted in 7 different files.