GitLab

* Add LayoutLMForQuestionAnswering model

* Fix output

* Remove TF TODOs

* Add test cases

* Add docs

* TF implementation

* Fix PT/TF equivalence

* Fix loss

* make fixup

* Fix up documentation code examples

* Fix up documentation examples + test them

* Remove LayoutLMForQuestionAnswering from the auto mapping

* Docstrings

* Add better docstrings

* Undo whitespace changes

* Update tokenizers in comments

* Fixup code and remove `from_pt=True`

* Fix tests

* Revert some unexpected docstring changes

* Fix tests by overriding _prepare_for_class
Co-authored-by: Ankur Goyal <ankur@impira.com>