Along with the requirements change, there are also needed changes
roles_path and ansible_python_interpreter variable handling, for
some reason latest Ansible did not like current configuration.
Change-Id: I5fc78d479e276711365ea497edd4d3e38cacd650
This change adds a flag 'generate_keypair' that makes the
role to generate an ssh keypair, create an OpenStack keypair with
it and all the servers of the play will have that key baked in.
The folder, key type and key length are also configurable.
Change-Id: Iccbec24e9834c1fa03da8add94e069f622024537