Caffeine – Make list of available "active for"-times configurable in GUI [Feature Request]

Please add a GUI way to edit the list of available "active for"-times in Caffeine.

Right now there's 1h, 2h, 4h, 6h, 8h, 24h. 
I would like to see e. g. 10h, too.
Other users will prefer other options that are currently not available.

I am aware that Caffeine offers many more options from the command line. That just doesn't work well / feel right for some users incl. myself.

The improvement could be added in different ways:

• An editor to add / remove entries from the list (with the option to restore default list)
  
• An option to enter an "active for"-time manually, then remember that value (or the last n manually entered values)
  
• In generalised form: An option to make all command line options available from the GUI, to save and open configuration files