6.0 Changes

- Mists scripts use estimated level 90 stats.
- ep_helper() doesn’t calculate the EP of the normalize stat, it’s
instead left at 1 to improve performance.
- Updated damage formulas, and various mechanic values.
- Ambidexterity perk moved to combat init method.
- Various buffs, procs and stat values/conversion have been updated to
use datamined and/or estimated values.
- Removed outdated class_data.py data.
- multiplier_from_rating() methods now force floating point when
possible.

Note: Once again, ignore darkmantle stuff, and priority_list.py stuff.