List all available locations

def avail_locations(call=None):
    '''
    List all available locations
    '''
    if call == 'action':
        raise SaltCloudSystemExit(
            'The avail_locations function must be called with '
            '-f or --function, or with the --list-locations option'
        )

    ret = {}
    conn = get_conn()
    response = conn.getCreateObjectOptions()
    #return response
    for datacenter in response['datacenters']:
        #return data center
        ret[datacenter['template']['datacenter']['name']] = {
            'name': datacenter['template']['datacenter']['name'],
        }
    return ret