Added row counts to table titles. Added read-only Reference column to measure...

Added row counts to table titles. Added read-only Reference column to measure table to denote whether a measure is a reference or not. Fixes #368.

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@3724 41f8697f-d340-4b68-9986-7bafba869bb8