- add defs get_free_names, raise_name_intersections_if_exist,upload_dir, upload_dirs to pintcloud api
- add defs is_valid_pcd, is_valid_format to pintcloud
- add def get_max_frame_idx
- update def _upload_bulk_add to process meta and frames correctly
- fix progress_cb and add closing BufferedReader after upload in def _upload_data_bulk
- fix typo in docstring of def is_valid_format in video
- add tests