OrthogonalSlice is now Slice since we plan to support non-ortho slices.
TomViz now has non orthogonal slices.
Add in a custom non orthogonal Module that supports rgb coloring.

The widget is based off of vtkImagePlaneWidget. Currently we don't have
the color transfer function hooked up properly, as modification aren't
properly passed to the Widget.
Lookup table modifications now are properly reflected in the plane widget.
Make deleting the slice module disable the slice widget.
Cleaned up the ModuleSlice implementation to be easier to understand.
Setup the color plane widget to color char arrays using the lookup table.

Previously we treat char arrays as pre-existing grey-scale color tables.
ModuleSlice now tells the color lookup table the correct data range.
Remove the ability to pan or scale the plane widget.

I am removing functionality from the widget that we don't need so that
the complexity of the class is reduced. Afterwards we will add in our
new features that we need.
Remove the cursor,text, and window leveling from the plane widget.
Remove the ability for the widget to spin.
Remove the ability to freely move the widget.
Setup a red background for slice to make it easier to detect what to remove.
ModuleSlice now compiles in debug mode as asserts are in the right scope.
Change the rotate implementation to be easy to understand.
PlaneWidget now clips section of the texture that lay outside the bounds.
cleanup some of the more hard to read section of vtkColorImagePlaneWidget
Make the plane have no box border when the user isn't picking it.
Updat the plane widget to use an arrow widget for rotation.
Extend the clip long enough to cover the entire volume at all times.