Fix Globus library list for Mac OS X 10.8. #3137

Mac OS X 10.8 (and 10.6) doesn't have libltdl in /usr/lib. Thus we build
our own for Globus to use, and we have to include it on the link line.
Add basic test for condor with ENABLE_CLASSAD_CACHING=true.
===VersionHistory:None===
Merge branch 'V7_9_5-branch'