Tempest API tests: Add ipv6 attribute tests

Implements blueprint ipv6-subnet-attributes

Change-Id: I7f8358f4fc507cc2ea73ebbf8a7ff25f0e8306fe
Add 'Member' role to all created users

When cloud's glance service configured to use swift for storing data
then user works with glance must have operator_role.

Change-Id: Idd92640d5d6b1957aa6ac84a4124e0b2eb5f26b1
Closes-bug: #1316166
Add 'id' to the server group cleanup list, not body

Change-Id: If55855d6c104dcd01d648688d2b9d7c2953a9a25
Closes-Bug: 1333965
Merge "Tempest API tests: Add ipv6 attribute tests"
Merge "Add 'id' to the server group cleanup list, not body"
Merge "Add 'Member' role to all created users"