Potato Spellbooks Tweaks

Replaces the formula for magic resistance from Iron's Spells and Spellbooks with a less powerful one.
This is most useful in modpacks, where magic resistance can quickly get out of hand and make any magic damage almost zero.

This mod "works" when present only in the server-side, but it will cause things to display incorrectly to players in the server that don't have the mod.
Also, if the mod is present only client-side, it will cause that person's game to crash.
Basically, this mod must be present in client and server so that no one has any issues.

To-do:
- Add a config file to edit formula (done)
- Make so the formula can be entirely edited in the configs (instead of just some values)
- Tweak some "problematic" spells (working on it)
- Add config to change those spells

"Maybe" aditions:

• Add tweaks to curios items via config
  (it is possible to edit other items via KubeJS - check their wiki and discord)