Adds new_prepare.bat

Fancy map backups now with 150% more choices
Adds new_clean.bat

Fancy map cleaner now with 150% more FANCY.

Essentially:
Asks you which map to clean out of ../maps/
Yells at you if the map isn't backed up
Yells at you if what you chose isn't actually a map
Runs the MapPatcher.jar thing
Merge pull request #3167 from Kilakk/bleeding-edge-freeze

Adds fancy batch files for preparemap and cleanmap in maptools