Add sup-config menu choice
Don't use the deprecated Enumerator.new
Make sure special labels' folders are created
Don't include non-maildir folders

Including non maildirs breaks things at the indexing step
Allow to fail on invalid maildir ids
rename Singleton to SupSingleton to sidestep conflicts with ruby's Singleton
Merge pull request #271 from gauteh/supsingleton

Yep !
Add warning about possibly creating special folders
Protect automatic maildir creation
Merge #267: Polish and fixes
Merge branch 'develop' into maildir-root