Remove usage of admin_token

* Added new tenant/project: services
* Added two new users with admin roles to 'services' project:
  ostf and nailgun
* Use generated passwords for ostf and nailgun keystone users and
  remove admin_token
* OSTF and nailgun will use their users to validate keystone tokens
 instead of admin_token
* Added new services and endpoints for keystone, ostf, nailgun. Now
 it's possible to use keystone service catalog to discover their URLs

DocImpact
Change-Id: Ibf64d83e7507b6b5d68d3d95837940e062d2aa31
Implements: blueprint access-control-master-node-improvments
Merge "Remove usage of admin_token"