Step #124 in the Expanded Vanilla list
Featured In Mod Lists:
Expanded Vanilla (#124), I Heart Vanilla (#16), I Heart Vanilla: Director's Cut (#20), Graphics Overhaul (#189), Total Overhaul (#252)
This tool is absolutely essential if you use a mod that deals with leveled lists, which is very common. If you don't know what that is, and you use more than a handful of mods with plugins, it is probably worthwhile to use this.
This link should have everything you need to know.