New build 5/25: equipment system, bug fixes

This new beta build introduces the "Equip" menu, so you can finally equip those weapons and armor.  It contains a variety of small improvements and fixes.

I've also started working on the cutscenes after the first boss battle.  Not a lot to see there just yet, as it's still a work-in-progress, but there's some content there.

Major changes:

• Added Equipment system
• Added and replaced some crafting recipes
• Made enemy AI more interesting.  Scubashrub will sometimes heal its allies, and the Eviscerator will sometimes cast a spell called Eviscerate, which deals Shadow damage to all enemies
• Instead of always inheriting exactly 2 skills, fused demons can now inherit somewhere from 1 to 4. The number depends on how much you've used the ingredient demons in battle (1 if neither of them has leveled up, ranging up to 4 if both demons have leveled up 2+ times each)

Minor changes:

• Healing spells heal more now, based on the casting monster's Magic power
• Fixed bug with Heal All spell
• Fixed most of the bug where UI was messed up in non-1080p resolutions. Still messed up when selecting a monster in the main menu, but otherwise should be good.
• Fixed music bug
• Various other small bug fixes and quality of life improvements