Replace Confirmations

[lenemter]

Fixes #76

It's a bit broken for now.

[lenemter]

We need to change the confirmation types of gala, sound indicator and power indicator.

1. Gala should give different confirmation types for sound and brightness.
2. Gala sound type and sound indicator types should match. This should be done in case user changes sound using media keys and then changes sound by scrolling on the Wingpanel icon.
3. Same thing for power indicator.

[lenemter]

@Marukesu I tried to use setter. Can you check please if that's what you had in mind?

[Marukesu]

1. Gala should give different confirmation types for sound and brightness.
2. Gala sound type and sound indicator types should match. This should be done in case user changes sound using media keys and then changes sound by scrolling on the Wingpanel icon.
3. Same thing for power indicator.

this is broken because ShowOSD doesn't have anything that can be thought as "type", and even if we add something that can be saw this way in Gala, GSD won't use it anyway.

i think the path forward here is moving out from GSD's MediaKeys plugin. and having the indicators deal with the keyboard shortcuts. that would have the plus that we won't end with a notification when the indicator popover is open, like happens now.

[Marukesu]

Works as expected.