Affine2D: Remove * operator, it's unused.

RendererBase: Add ComputeCamera() as a virtual function. Add strips parameter to TotalIterCount().

Renderer: Implement ComputeCamera() as an override.

SpatialFilter: Ensure filters that are too small are made large enough to create.

FinalRenderDialog: Add estimated iters table row and populate on all UI updates.

FractoriumParams: Zoom was not being saved, loaded. Fixed.

GLWidget: Prevent mouse wheel event from being passed to the scroll bars. It should only affect the scale.