Bump clutter required version to 0.9.6
Bump clutter required version to 0.9.6

We now depend on clutter 0.9.6 as we are using the cogl_flush() symbol.

GNOME/clutter-gst,skinkie/clutter-gst,ystreet/clutter-gst,GNOME/clutter-gst,GNOME/clutter-gst,skinkie/clutter-gst,skinkie/clutter-gst,ystreet/clutter-gst,lubosz/clutter-gst,lubosz/clutter-gst,GNOME/clutter-gst,ystreet/clutter-gst,lubosz/clutter-gst,ystreet/clutter-gst