Add visibility parameter to Surface

[griffin28]

For a few SciVis apps like ParaView and VisIt you can toggle the visibility of different surfaces on and off. I think it would be more efficient, especially for back-ends like VisRTX, to update a visibility parameter on the surface instead of removing/adding the surface when the visibility flag is turned off and on.

This could potentially avoid costly memory copies from host to device. In practice, the visibility flag is used often to show/hide different parts of the dataset.

Name	Type	Default	Description
visibility	UINT8	1	surface visibility flag (0 means not visible, 1 means visible)