Install qpdfviewer instead of Document Viewer as default to put pdfs in half of the screen with: start+arrow

https://forums.linuxmint.com/viewtopic.php?t=160764
Document Viewer does not allow one to make the pdf viewing window/application screen smaller than some value. This prevents me from shifting the pdf viewer into a half of the screen with: `start+right arrow`.

```
sudo apt install qpdfview
```
does allow this.

Reminder, zooming in and out there is `Ctrl+up` and `Ctrl+down`, instead of `Ctrl+plus` and `Ctrl+minus`.
Refresh: `Ctrl+R`.

- [ ] Also include setting infinite zoom. Related for other program
```
gsettings set org.gnome.Evince page-cache-size 2014
```
Source: askubuntu