ziptied X-end

UPDATE :
There was a big fail on the x-end-motor I corrected + increased space for GT2 belt


This is a slight remix of [Xoan's i3 ziptiedish x-end](http://www.thingiverse.com/thing:94867) and Josef prusa's vanilla prusa where :
- even the LM8UU are ziptied ! (2.5mm zipties work fine for this)
- added a 10 mm hole for the Z-axis to move freely as I'm rather using [my thing 1147671](http://www.thingiverse.com/thing:1147671) for leadscrew anti-wooble purposes.
- added a little hole on the