Gnome-shell metapackage

[d . 4 . n . 1]

Hi Guixs,

do you think about create a metapackage to gnome-shell? How do I change 
slim/wicd to gdm/networkmanager?

I installed gnome-shell in my guixsd but I can't login. There's error 
with something.

Thanks.

--
Daniel Pimentel (d4n1)