Migrating Nether from Bukkit to Vanilla

Bukkit splits the world folder for some reason into world, world_nether, and world_end (WHY?). I want to put these back together into one world folder as if it was on a vanilla server (for use with MCEdit).

I know you're supposed to rename world_nether to something (either DIM-1 or DIM1 I think) and put it back into world, doing the same thing with world_end and a different name, but what am I supposed to rename it to? I have found only conflicting answers online.

 

start a single player world, go to the nether, go to the end, then save and quit.

look in your world saves folder and see what vanilla has the folders named.

actually do it one by one. start the world, go to the nether and wander around a bit so it generates mca files.

quit and see which folder has the mca files and that should be the name that is for the nether.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.