Add fuzzy-text filtering for select attributes

[LaCuneta]

If you have many choices in a select attribute, but aren't sure where in the list or the exact spelling of the choice you want, a fuzzy search would really help narrow things down. This would be made even more useful if #19 is implemented and options can be hidden many levels deep in a folder structure. Of course, this should have an option to be disabled in cases where it's not desired for any reason.