Add cover art to browser

[Tamriel]

I really like the clearness of how iTunes shows an artists songs:

You too?

[Lalopx]

Love the way it displays an Album Artist and upon selection shows every album by year with its propper album art and tracks by the side. Would love to work on acheiving something like this for OSX version of Quod. Or Somthing like Musicbee in windows.

[Tamriel]

Probably I could do that with Qt, but Quod Libet is done in GTK, and I don't know any of that.

[declension]

@Tamriel I too like the attached look and feel, but which browser are you proposing be modified, or are you proposing a new Browser entirely?

A long time ago there was an experimental album similar(ish) to this I seem to remember.
If this entirely removes the songlist, this would be quite different to all other current Browsers and therefore a lot of extra work I'd say (@lazka would have a better idea here).

Getting the performance (scrolling, etc) good enough may also be challenging given the number of tracks we try to support.

Note there's #241 too, though that's different.

[Tamriel]

I propose it for the browser titled 'browser' (image). I would like to choose at the wheel at the top right, if I want to see covers or a list.
I think performance is no problem as long only a subset of items is displayed, e.g. just the albums of one artist.