replace framebuffer.h include with forward declaration

instead of including framebuffer.h almost everywhere, replace it with
class CFrameBuffer forward declarations and/or generic system includes.
Add a hack to define fb_pixel_t to config.h (one reason for
framebuffer.h includes was the fb_pixel_t define)

src/gui/lua/luainstance_helpers.h

@@ -21,6 +21,7 @@
 #ifndef _LUAINSTANCEHELPERS_H
 #define _LUAINSTANCEHELPERS_H
 
+#include <map>
 
 //#define LUA_DEBUG printf
 #define LUA_DEBUG(...)