[Cinnamon] Use original panel separator design

[Greyfus]

I do not like how the separator is just a line. Is there a way to make it look more like XP with the original feel of it? I know the old CinnXP has the separator, but I do not know the etiquette for that. Yours is more up to date and I like it more, just that one part bothers me.

[Elbullazul]

I'll see what I can do next time I work on this