Scripts/Halion: Fixed Soul Consumption's pull effect.

Thanks to Winterfell for pointing out the issue.
Core/Entities: correct creature damage, offhand damage should work too
* todo: some creatures need dmg_multiplier update in creature_template
DB/Spells: remove duplicate/invalid entries from spelldifficulty_dbc
* For new entries: use spellid0 as id to avoid conflicts with dbc file