Watch folders for deleted files and delete from Nextcloud

### Is your feature request related to a problem? Please describe.
Currently I can use Markor to edit notes and those are synced when I open Nextcloud Client and sync the folder. But If I delete a file outside Nextcloud Client that file will just be restored by Nextcloud Client sync.

### Describe the solution you'd like
A watched folder like the AutoUpload folder which will also delete files.

### Describe alternatives you've considered
Syncthing

### Additional context
I would use this to handle external note editor app syncing so I can delete a note via native android methods or 3rd party app without having to delete in the Nextcloud Client app.