Part Wheel Positions Function

# Function Overview
Name: Wheel Positions Function
Function: allows the part to store more WheelSlots
From FVTM: yes

The Wheel Positions Function allows the part to include more WheelSlots
into a Vehicle.

Example config:

    "Function": {
    	"id": "fvtm:wheel_positions",
    	"wheel_positions":[
            { "x":  0, "y": -16, "z": 0, "id": "test_wheel",    
              "radius": 8, "drive": false, "y_rot": -90,    
              "steering": true, "required": false }
    	]
    }

Here an overview of the available fields:

• id - the id of the function, it is fvtm:wheel_positions
• wheel_positions - an JSON array with JSON objects having the wheel slot data
  on how to fill them out, check WheelSlot