Fix a runtime for Mloc

(mloc is so lazy)
Also makes custom item spawning a tiny bit nicer!
file will only be loaded once, instead of every time someone spawns
Fixes #4756

removes the getrev stuff because it's svn and old and I couldn't get tg's stuff to work :c
Fixed #4697 while still trying to make it work

a bit messy but I don't know a better way to do this
Fixes #5088

also fixes more runtimes that mloc gave me
Fixes #5285

will it never end ;~;
fixed some weird slime runtime that's been around forever apparently
Merge pull request #5284 from boopcat/happydrones

more fixes!