Add Iron's Spells and Spellbooks compatibility

[SimplyChloe]

As mentioned in the title.

Unique weapons from Simply Swords that have some form of elemental damage ability scale that damage with the spell power the player has, indicated by an icon in the weapon's tooltip.
For example, in this screenshot, the tempest's ability damage scales with frost and fire spell power.

[jay-jay0101]

I planned to add this in the 1.21.1 port, but I guess with everything that changed I forgot to. I'll try add it next time I update, which should be in a month or so when I have time.

[KnightmareFyl]

I thought simply swords only had compat with simply skills and by extension spell engine? Do they use the same spell power attribute???