Improve edit_prefix input sanity checking
Improve edit_prefix input sanity checking

Simple, concise, functional. That's how we like it!

SoundGoof/NIPAP,fredsod/NIPAP,garberg/NIPAP,SpriteLink/NIPAP,SpriteLink/NIPAP,garberg/NIPAP,fredsod/NIPAP,ettrig/NIPAP,bbaja42/NIPAP,ettrig/NIPAP,ettrig/NIPAP,SpriteLink/NIPAP,plajjan/NIPAP,SoundGoof/NIPAP,plajjan/NIPAP,SoundGoof/NIPAP,bbaja42/NIPAP,SoundGoof/NIPAP,garberg/NIPAP,fredsod/NIPAP,plajjan/NIPAP,fredsod/NIPAP,ettrig/NIPAP,ettrig/NIPAP,SoundGoof/NIPAP,SpriteLink/NIPAP,SpriteLink/NIPAP,plajjan/NIPAP,fredsod/NIPAP,bbaja42/NIPAP,SoundGoof/NIPAP,plajjan/NIPAP,bbaja42/NIPAP,bbaja42/NIPAP,fredsod/NIPAP,plajjan/NIPAP,SpriteLink/NIPAP,garberg/NIPAP,bbaja42/NIPAP,garberg/NIPAP,ettrig/NIPAP,garberg/NIPAP