Idler clamp

Thx [schlotzz](http://www.thingiverse.com/schlotzz/about) for the original design for this direct drive extruder. Mainly I did get one of the idler to break the pressure on the bearing was too great and the pin snapped I then wanted a simple add on without changing anything from the original design like this anyone who already got this extruder can use this little clamp. You'll just need to use a bit longer screw a 20mm to 25mm for the swivel and a 16mm to close the idler and clamp together.