Neutron&Designate DNS integration - some enhancements

1) Increase "build_timeout" for stability purposes
2) Extend "test_port_with_publishing_subnet", so it will now
   cover IPV4 missing test case, it means:"subnet-dns-publish-fixed-ip"
   is set to True for IPV4 subnet.
3) As of now "reverse zones" created by Neutron for testing
   purposes aren't cleanuped.
   This patch adds "resource_cleanup" that detects "arpa"
   zone created by Neutron within the test and removes it.
4) Minor code changes:
   - Using provided by Designate Plugin "wait_until" to reduce
     some code lines
   - Giving names to created instances for debug purposes

Change-Id: I8aa238cfc73d67906e7d3f769a8a10423b2247cc
1 file changed