more ui polishing: working sets

[David Nolden]

I didn't see the actual message, and cannot find it on the mailing list. When 
did you send it, and can you send it again?

Basically, I do think working sets could be improved further, but I also feel 
they work quite well the way they are now, and we have more serious UI issues 
in the much more important "building" area that should IMO be adressed with a 
higher priority (the connection between the "Project" menu, "Buildsets", and 
the project tree view).

Greetings, David