In qmos, added a 'Phase Angle' column to the list of opened files. This column...

In qmos, added a 'Phase Angle' column to the list of opened files. This column behaves exactly like the other camera angle columns with respect to visibility and sorting. Fixes #1093.

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@4940 41f8697f-d340-4b68-9986-7bafba869bb8