RaptorJIT load: follows symlinks recursively and loads same audit.log multiple times

[eugeneia]

In case of named Snabb programs their SHM directories contain a name symlink that leads to the same directory. When pointing RaptorJIT load: at such a SHM directory it will try to load the audit.log ten times instead of only once.

Possibly we should either not follow symlinks at all or somehow detect if we attempt to load the same audit.log and avoid that.

[lukego]

Had a first attempt at fixing this but the primitive FileReference>>isSymlink doesn't seem to be working. Could be a build issue with the VM. Have to resolve that first methinks.