PROG: Cleaned up some of the comments in ResourceGet.cpp file used by the...

PROG:  Cleaned up some of the comments in ResourceGet.cpp file used by the edrget application, and removed a cout error statement which should not have been there.  References #4771.

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@7811 41f8697f-d340-4b68-9986-7bafba869bb8