Paper2remarkable

* Print to log whether removing arXiv stamp was successful.
* Fix bug that failed to correctly detect the pdf tool
([42](https://github.com/GjjvdBurg/paper2remarkable/issues/42)).

* Bugfix that makes removing the arXiv stamp more robust.

* The Dockerfile has been updated to use a more recent version of Cairo
([35](https://github.com/GjjvdBurg/paper2remarkable/issues/35)). Thanks to
ClaytonJY.
* We've added support for optionally using qpdf instead of pdftk
([36](https://github.com/GjjvdBurg/paper2remarkable/pull/36)). Thanks to
delaere.
* Resolving redirects has been improved, which solves an issue for the
Springer provider
([38](https://github.com/GjjvdBurg/paper2remarkable/pull/38)) and an issue
with some arXiv urls
([39](https://github.com/GjjvdBurg/paper2remarkable/pull/39)).
* Unit tests were added for the provider selection.
* The code that removes the arXiv stamp has been improved
([40](https://github.com/GjjvdBurg/paper2remarkable/pull/40)).
* Tracebacks have been disabled outside of debug mode, showing clearer errors
([41](https://github.com/GjjvdBurg/paper2remarkable/pull/41)).

* Be more robust against missing pdftoppm executable.

* Fix bug for when the shrink operation returns bigger files
([33](https://github.com/GjjvdBurg/paper2remarkable/issues/33)).

* Add the option to not crop the file at all
([28](https://github.com/GjjvdBurg/paper2remarkable/pull/30)).
* Add the option to right-align the file so the menu doesn't overlap
([28](https://github.com/GjjvdBurg/paper2remarkable/pull/31)).
* Bugfix for validation for the JMLR provider