Optional buttons-controller?

[sashasochka]

Hi,
wouldn't it make sense to make buttons-controller optional? There 3 reasons why it might make sense to do that:

• you don't always want to have a controller but here you need to specify it. I use just angular.noop for this purpose.
• even if you have buttons you can use on-change event to get editor's value instead of buttons-controller
• button-controller has quite specialized name which makes it look like it's just for buttons.