Support for IPv6 tests for API

Added IPv6 everywhere where it's relevant in network API tests.
Partially implements: blueprint ipv6-api-testing-parity

Change-Id: If2baaa3f2433b88ea4a3ed6dbee61ad6ee9ad3b0
Add scenario test for swift-proxy ceilometer middleware

This test creates a swift container, puts something in it
and then checks for samples stored by ceilometer which were
created by notifications from the middleware. test.call_until_true
is used to loop across multiple requests for samples in order
to be flexible in the face of latency on the notifications bus.

Change-Id: I07316db1f51d0562919ed2a50f002011944bfdb1
Merge "Support for IPv6 tests for API"
Merge "Add scenario test for swift-proxy ceilometer middleware"