* utils_ner: do not add extra sep token for RoBERTa model * run_pl_ner: do not add extra sep token for RoBERTa model
see context in https://github.com/huggingface/transformers/pull/4223
* Created using Colaboratory * [examples] reorganize files * remove run_tpu_glue.py as superseded by TPU support in Trainer * Bugfix: int, not tuple * move files around