[Open Assets] Custom Peel-out 1.5

It's been a while, but recently I've been playing SRB2 Generations, and one bug in particular really bothered me, you could use the peel-out during the stage select screen. This version is a simple fix for that, and will probably be the last version of this script.

Cleaned up some of the code to minimize redundancy.

Changelog​
Amy and Fang fixed! Fixed Peel-out not working properly with Amy and Fang.

Minor code refactoring and bug fixes.

Spoiler: CHANGELOG

• Renamed local functions, removed those P_ prefixes I added for no reason;
• Better compatibility with my Custom Boost script;
• Removed a stupid comment I added about not needing to give credit;
• Added split-screen commands.