Depend on Vala 0.16.1
Depend on Vala 0.16.1

We are using vfunc accessors for Widget.get_preferred_height/width which have
been added to this version.

https://bugzilla.gnome.org/show_bug.cgi?id=678072

GNOME/egg-list-box,GNOME/egg-list-box,GNOME/egg-list-box