Fidget Cube Remix

I really liked the idea behind the printed fidget cube, and after printing and using CThig's design for a few days (http://www.thingiverse.com/thing:1844556), I thought I could improve some aspects of it. The size should now be correct for putting into slicers, the wheel has a finger-divot instead of a post to spin, and has a circular internal 'clip' so that it doesn't fall out, the tunnel has two sizes of entry both now smoothed, the slider can be printed directly on the piece (just be extremel