* examples: add keep_linebreaks option to text dataset loader for all CLM examples
* examples: introduce new keep_linebreaks option as data argument in CLM examples
* Fix tied weights on TPU
* Manually tie weights in no trainer examples
* Fix for test
* One last missing
* Gettning owned by my scripts
* Address review comments
* Fix test
* Fix tests
* Fix reformer tests
* Validation split percentage to be used for custom data files also
Issue same as https://github.com/huggingface/transformers/issues/12406 fixed for pytorch branch run_mlm.py
* Validation split added in the right place
* Update run_clm.py
* validation split added for custom files
* Validation split added for custom files
* Update run_plm.py
* fixed validation split for custom files as input for pytorch examples in lm
* Update run_clm_no_trainer.py
* args modified
* Base move
* Examples reorganization
* Update references
* Put back test data
* Move conftest
* More fixes
* Move test data to test fixtures
* Update path
* Apply suggestions from code review
Co-authored-by: Lysandre Debut <lysandre@huggingface.co>
* Address review comments and clean
Co-authored-by: Lysandre Debut <lysandre@huggingface.co>