Roles and hierarchy implementation

    1.project_admin role is added for a self registered user.
    2.Implemented identity panel for project_admin
       2.1 Added Projects link with add project ,associate users,modify,delete users functionality
       2.2 Added Users link with add user,edit user and delete user functionality

    Files changed
    * openstack_dashboard/dashboards/project/projects/
         +Adding projects directory for the identity panel for project_admin
    * openstack_dashboard/dashboards/project/users/
         +Adding users directory for the identity panel for project_admin
    * openstack_dashboard/api/keystone.py
         +Changes admin flag for project admin access to apis
    * openstack_dashboard/dashboards/project/dashboard.py
         +Added new identity panels

    Note:The tenant_admin functionality will only work with changes in keystone/policy.json,cinder/policy.json ,neutron/policy.json and nova/policy.json attached in the bug

    Pending tasks:
    1.Modify projects
    2.Testing on the add,delete,modify fuctinality

    Bug: https://bugs.launchpad.net/jio/+bug/1319258
    Implements: blueprint roles-and-hierarchy
In certain conditions while testing ,encountered role_list to be NULL and pushing was causing an error .That is why this condition is introduced.