Automatic discovery of TripleO Overcloud hardware

-geting IP addresses from Undercloud nova, allowing
 to poll all Overcloud nodes via SNMP
-adding support of basic auth, user_name and password
 used in TripleO by default

Change-Id: I189dbba9579055c8a1a878a769760a72e9174c6d
Enable some tests against py33

Change-Id: Ibaf141784cbe08230cdb8f9aba3e5f376e7e1b93
Merge "Automatic discovery of TripleO Overcloud hardware"
Merge "Enable some tests against py33"