Rep 2x E3D upgrade

I loved the 2x e3d upgrade but was worried the fan ducts were going to break with all the shaking and didn't think they snapped on very tightly. Went ahead and upgraded and redesigned.

And then i just kept going, this is a full redesign of cadsys' e3d upgrade for the 2x:

hardware:
2 x M3x18 or longer - carriage to hotend assembly
3 x M3x12 or longer - top cap to hotend assembly
2 x M3 washer - optional for the top cap
1 x good ol popscicle stick - X axis endstop
5 x M3 nuts
k type th