Changed way network is notified of ignored points and measures. References to...

Changed way network is notified of ignored points and measures.  References to ignored points and measures are now maintained in ControlCubeGraphNodes

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@2396 41f8697f-d340-4b68-9986-7bafba869bb8