(PROG) Modified InterestOperator::FindCnetRef to report status on number of...

(PROG) Modified InterestOperator::FindCnetRef to report status on number of points instead of number of measures. Modified ControlNetValidMeasure::ValidStandardOptions to initialize the mdDnValue variable. Fixes #2040

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@5741 41f8697f-d340-4b68-9986-7bafba869bb8