LibDraw: Introduce (formerly known as SharedGraphics.)

Instead of LibGUI and WindowServer building their own copies of the drawing
and graphics code, let's it in a separate LibDraw library.

This avoids building the code twice, and will encourage better separation
of concerns. :^)

Libraries/LibGUI/GEvent.h

@@ -3,8 +3,8 @@
 #include <Kernel/KeyCode.h>
 #include <LibCore/CEvent.h>
 #include <LibGUI/GWindowType.h>
-#include <SharedGraphics/Point.h>
-#include <SharedGraphics/Rect.h>
+#include <LibDraw/Point.h>
+#include <LibDraw/Rect.h>
 
 class CObject;