* clutter-box2d.cpp: improved text.
* clutter-box2d.cpp: improved text.

clutter-project/clutter-box2d,GNOME/clutter-box2d,GNOME/clutter-box2d,clutter-project/clutter-box2d,GNOME/clutter-box2d,clutter-project/clutter-box2d,clutter-project/clutter-box2d,GNOME/clutter-box2d