[addons] Add and refresh icons.

Simplify and remove branding.
Also add icons to where none or any better icons existed

There's a few still left on the forge.

Missing atm is all the screensavers addons and a few of the others, they will eventually be done.
Reason is all these are now svg and most of these don't have any logos or even vectors to begin, so it all has to be done from scratch.