E3D Fan duct and Mendel 90 X carriage for LM10UU

These are my changes for E3D hotend on Mendel 90 "Sturdy" variant with LM10UU bearings and T5 belt. There isn't room for the normal fan duct so I put it on the X carriage like http://www.thingiverse.com/thing:157992 . You can use a normal thickness 40mm fan.

To fit the E3d hotend, the extruder needs a more shallow indent, so the wades extruder was modified. No openscad file because I changed hot_ends.scad function jhead_groove_offset() = 3.8;

The included fan duct has thin lines of suppor