Python 3 preparation: update tokenize use in cgitb.py. Note that the same interface that has changed incompatibly is also used in tools/pygettext.py. That file also needs fixing, but this patch does *not* attempt such a fix.

try:
    # Python 3+.
    from xmlrpc import client, server
except ImportError:
    # Python 2.
    import xmlrpclib as client
    import SimpleXMLRPCServer as server