a more dynamic Applet::formFactor()

[Giulio Camuffo]

> i'm not sure formfactors should be freely assigned, they are born as the
> containment formfactor.
> in your case it should be the containment that is Horizontal i think (even
> fixing horizontal regardless of the location, so even in the desktop)

But if i put an applet directly on the desktop, outside any group, the right 
formfactor is Planar. 
It is true that popup applets expand even on Horizontal or vertical form 
factors, but setting the desktop form factor to horizontal seems to me a bit 
like a workaround.