didnt commit this patch because curves are generally better to create a shape to lathe however now that curves can have modifiers applied to them I think its good to have this.
Added options to offset the lathe so it can work like the screw tool as well.
- optional object for axis which also controls the center point.
- screw offset so rather then just lathing this can work more like the screw tool.
- screw optionally using the object distance along the axis.
- iterations so the screw can be applied multiple times.
tested to work well with curves.