Fixed following errors:
-line 58: when you start new game as farm manager or start from scratch
-line 438: when detaching PTO from trailer with PTO function
-line 250: when start tipping with trailer with PTO function and no PTO attached
-line 271: when attaching two conveyor belt (or any with driveable spec)
-line 491: when detaching implement from attacherVehicle with no MA spec.