SCAnimation - classes for procedural animation, both realtime and NRT

A couple of classes for doing procedural animation. SCDraw is intended

for primarily for non-realtime use, although it does have a preview capability

that runs in realtime. SCDrawServer is only realtime. 

At the present time, both classes are Mac only. In the case of SCDraw, this is

because SCImage is used for rendering the image sequence.  In SCDrawServer,

SCNSObject is used to hide the cursor (if desired) in fullscreen mode.