Add python-keystonemiddleware package to OSTF spec

OSTF now requires keystonemiddleware package to use it
instead of outdated keystoneclient.middleware

Update python-keystoneclient version to match version in
our repos

Change-Id: I32848ccd2279c1467818e1ff9e1a19becc9f7ae7
Implements: blueprint access-control-master-node-improvments
Related-Bug: #1383616
Merge "Add python-keystonemiddleware package to OSTF spec"