Merged r6980 (gsl config update for linux) into IPCE, fixes dynamic loading...

Merged r6980 (gsl config update for linux) into IPCE, fixes dynamic loading issue. Removed Fedora21 specific config file to match v006LibrariesV2.

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/branches/ipce@6982 41f8697f-d340-4b68-9986-7bafba869bb8