Change shape/color of the control point being edited in the CubeDnView and...

Change shape/color of the control point being edited in the CubeDnView and Footprint2DView.  Update both views when control point is created or deleted.  Fixes #5007, #5008.

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/branches/ipce@7908 41f8697f-d340-4b68-9986-7bafba869bb8