[sugar] demo4 branch merged

[Marco Pesenti Gritti]

Gonzalo Odiard wrote:
> libwnck need gtk-doc (i have updated the wiki) and intltool >= 0.35.0, 
> but fedora
> have intltool 0.34.2 :(
>

Ok, building libwnck is not strictly necessary... I fixed it so that if 
you have libwnck-devel installed it will not build it but use the system 
one.

Marco