GenericProjectManager improvements

[Niko Sams]

> I think thats the better idea, that way the project toolview can do the
> watching and just refresh the changed files or directories (if files/dirs were
> added/removed).
Where should I do the watching? The best would be in the ProjectManager - so
CMake/QMake can correctly handle their special nodes. But then the
ProjectManager
needs to know what is currently open. So the ProjectManagerView needs to emit
signals when the view changes. But how does the ProjectManager get
these signals?
I can't find the view-plugin as it doesn't have a special interface.

Niko