include standalone cogl-wayland-server/client headers

include standalone cogl-wayland-server/client headers

Because the wayland-server-protocol.h header includes symbols that
collide with wayland-client-protocol.h Cogl now provides top level
<cogl/cogl-wayland-server.h> and <cogl/cogl-wayland-client.h> headers so
that applications can ensure they only include one of the wayland
protocol headers in a particular compilation unit. This updates clutter
accordingly to include those headers.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>