Similar to the pinning introduced in
Ic465efb637c0a1eb475f04b0b0e356d8797ecdeb, use the "latest"
openstacksdk package and allow for passing of pinned versions if
required.
Update the devel test to also use the master of opensatcksdk
Change-Id: I4b437ca9024c87903bdd3569c8309cde725ce28e