GUI-129: support ssl cert verification for eucalyptus connections

converted EucaAuthenticator to use httplib (like boto) so that we could re-use the CertValidatingHTTPSConnection boto uses for cert validation.
Use EucaAuthenticator directly instead of going through views/__init__.py:get_connection()
Ah, guess Boto's docstring isn't entirely accurate then.  No big deal, we can leave this one as is.