Use keystonemiddleware package

keystonemiddleware package will be used instead of deprecated
keystoneclient.middleware module to authorize requests with
keystone auth_token
python-keystoneclient was left as a requirement to allow
usage of 'keystone' command and updated to new version

Change-Id: I525a4914dba31f7f0309900936ace01f9752866d
Implements: blueprint access-control-master-node-improvments
Related-Bug: #1383616
Depends: I90005ac4054cc585fd23c0e91cfcd51ef1ce6a9d
Merge "Use keystonemiddleware package"