Anet A8 - Blower & Sensor mount

This mount can support both the 50mm stock fan blower from the Anet A8 and the inductive sensor SN-04.
The blower high can be adjusted and i also redesigned the nozzle.

This are the offset inside the Skynet firmware:
**#define X_PROBE_OFFSET_FROM_EXTRUDER 27 // X offset: -left +right [of the nozzle]**
**#define Y_PROBE_OFFSET_FROM_EXTRUDER -50 // Y offset: -front +behind [the nozzle]**
**#define Z_PROBE_OFFSET_FROM_EXTRUDER -1.39 // Z offset: -below +above [the nozzle]**

Also chanche this parameter in the configuration_h file:
** #define BACK_PROBE_BED_POSITION 160**