LJ18A3-8-Z/BX 8mm z probe x carriage mount

had to make the mount hole larger because the sensor i got (from amazon: LJ18A3-8-Z/BX 8mm Approach Sensor Inductive Proximity NPN NO Switch DC 6-36V) was much larger in diameter. basically re-cad'ed nhambayi's to the size needed. also, to make room for this mount, had to redesign the bowden mount with no bottom on it, here: http://www.thingiverse.com/thing:1345429