Incarnasoul Alpha 18

Slimes and character relationship tracking (the first part of the overhaul I'm working on).

Changelog:

+ Fixed a load issue with some saves
+ Added manual value entry for sliders via clicking the current value label
+ Added character relationships
-> Currently these have very limited effects, but they should change over time and be affected by e.g. carrying out activities together
-> They can be viewed via the "Relationships" button when viewing a character
+ Allowed gluttony, pride, laziness and optimism to be mind written
+ Added slimes, along with Not Quite One and Slime Plague activities, Apply Slime Sample essence warping activity, Absorbed captive activity (Not Quite One/Absorbed/Monstergirl Realms Exploration critical failure), Slime Sample item and Slime Disease/Super Slime Disease 'curses'
-> Slime body trait effects allows slimes to meet certain appearance checks if their trait is one point off. This uses a new 'trait substitution' system, so there may be issues
+ Made some performance changes to improve various previews when dragging characters
+ Replaced loyalty trait checks with loyalty to player checks
+ Angel and demon images have been split out into a separate zip file