## Summary
It would be nice to switch back to the file list from an Reader activity
via a short back button press. This change adds an Reader option to
switch the default behavior, so a short back button press in the Reader
activity can now go back to the file list, and a long press on back goes
back to the home view. This does a fair bit of refactoring, introducing
a new constant for the ms limit.
* **What changes are included?**
- Changes to the translation
- Additional global Reader option
- Refactoring of the back button behavior in the Reader activity