test against the enum scoping problem I had.
Ocaml.cxx: Accidentally reintroduced the enum scoping problem, so I added
an example that will fail if this is ever broken again.
I encountered the actual problem in avifile.h
git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@5478 626c5289-ae23-0410-ae9c-e8d60b6d4f22