GitLab

The option `--do_lower_case` is currently required by the uncased models (i.e., bert-base-uncased, bert-large-uncased).

Results:
BERT-BASE without --do_lower_case:  'exact': 73.83, 'f1': 82.22
BERT-BASE with --do_lower_case:  'exact': 81.02, 'f1': 88.34

* Add QA trainer example for TF

* Make data_dir optional

* Fix parameter logic

* Fix feature convert

* Update the READMEs to add the question-answering task

* Apply style

* Change 'sequence-classification' to 'text-classification' and prefix with 'eval' all the metric names

* Apply style

* Apply style

* 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* remove run_tpu_glue.py as superseded by TPU support in Trainer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