Better File Dialog for Linux

[benjamin-kirkbride]

          TIL that it tk uses native file dialogs on not-linux...

Yes, agree completely with everything @rdbende said. My thoughts is it should work like this:

1. if windows or mac use default filedialog as now; if linux continue
2. check config to see what user wants to do; if no config set continue
3. try zenity
4. try kdialog
5. try tkfilebrowser (optional install?)
6. fallback to default tk.filedialog

Originally posted by @benjamin-kirkbride in https://github.com/Akuli/porcupine/issues/1358#issuecomment-1629805198