DEV-34837: Remove dependency on Leopard-only /usr/local/lib/libexpat.0.1.0.dylib.

On Mac, add libexpat[.0.5.0].dylib to apr_suite package. Update
libapr-1[.0.3.7].dylib and libaprutil-1[.0.3.8].dylib with versions that
reference this expat. Make viewer_manifiest.py copy expat dylib to app bundle.