Adds a simple versioning system that exports a timestamped copy of your current UFO.
Replicant saves everything into a directory called _archive, which it will create as a sibling of the working file if it doesn't already exist.
http://github.com/jackjennings/Replicant
Either install Replicant through Mechanic, or download the .zip file and double click Replicant.roboFontExt.