Return a list of available roles (keystone role-list)

    CLI Example:

    .. code-block:: bash

        salt '*' keystone.role_list

def role_list(profile=None, **connection_args):
    '''
    Return a list of available roles (keystone role-list)

    CLI Example:

    .. code-block:: bash

        salt '*' keystone.role_list
    '''
    kstone = auth(profile, **connection_args)
    ret = {}
    for role in kstone.roles.list():
        ret[role.name] = dict((value, getattr(role, value)) for value in dir(role)
                              if not value.startswith('_') and
                              isinstance(getattr(role, value), (six.string_types, dict, bool)))
    return ret