GitLab

* Add copyright everywhere missing

* Style

* debug env

* Restrict TF GPU memory

* Fixup

* One more test

* rm debug logs

* Fixup

This is the result of:

    $ black --line-length 119 examples templates transformers utils hubconf.py setup.py

There's a lot of fairly long lines in the project. As a consequence, I'm
picking the longest widely accepted line length, 119 characters.

This is also Thomas' preference, because it allows for explicit variable
names, to make the code easier to understand.

We add a script and a CI workflow to check that all download links
present in the source code are valid.