Removes Cogl from the repository

Cogl has now been split out into a standalone project with a separate
repository at git://git.gnome.org/cogl. From now on the Clutter build
will now simply look for a cogl-1.0 pkg-config file to find a suitable
Cogl library to link against at build time.

tests/conform/test-cogl-texture-pixmap-x11.c

@@ -7,9 +7,7 @@ static const ClutterColor stage_color = { 0x00, 0x00, 0x00, 0xff };
 #ifdef COGL_HAS_XLIB
 
 #include <clutter/x11/clutter-x11.h>
-/* This gets installed to a different location so a real application
-   would use <cogl/cogl-texture-pixmap-x11.h> */
-#include "cogl/winsys/cogl-texture-pixmap-x11.h"
+#include <cogl/cogl-texture-pixmap-x11.h>
 
 #define PIXMAP_WIDTH 512
 #define PIXMAP_HEIGHT 256

tests/interactive/test-box-layout.c

@@ -23,7 +23,7 @@
 
 #include <clutter/clutter.h>
 #include <cogl/cogl.h>
-#include "pango/cogl-pango.h"
+#include <cogl/cogl-pango.h>
 
 #define INSTRUCTIONS \
         "Press v\t\342\236\236\tSwitch horizontal/vertical\n"           \

tests/interactive/test-table-layout.c

@@ -5,7 +5,7 @@
 
 #include <clutter/clutter.h>
 #include <cogl/cogl.h>
-#include "pango/cogl-pango.h"
+#include <cogl/cogl-pango.h>
 
 #define FONT "Sans 12"