Reads cams conf from file and intantiate appropiate classes.
    Returns: an array of IpCam classes.

def load_cams(conf_file):
    """Reads cams conf from file and intantiate appropiate classes.
    Returns: an array of IpCam classes."""
    with open(conf_file, "r") as c_file:
        lines = c_file.readlines()
    cams_conf = [json.loads(j) for j in lines]
    cams = []
    for cam_c in cams_conf:
        init_params = __parse_args(cam_c)
        cams.append(cam_types[cam_c["type"]](**init_params))
    return cams