PYCBC-648 Minor Authenticator addition per RFC
PYCBC-648 Minor Authenticator addition per RFC

Motivation
==========
Add a couple functions to the Authenticator sub-classes, so someone
could query whether it does/doesn't support tls, per the RFC.

Modification
============
All the Authenticators (Password, Classic, and Certificate) have the
functions now, with hard-coded returns.

Results
=======
Nothing new - no added tests, but they all pass against the mock.

Change-Id: Ibc2f8bf1fd5db1038d6306ca2c964f88cf613507
Reviewed-on: http://review.couchbase.org/121223
Reviewed-by: Ellis Breen <9d8041ac7ead8d3e1f3217c04c7ed5e3098c2381@couchbase.com>
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

couchbase/couchbase-python-client,couchbase/couchbase-python-client