Reorganized core/ directory, it was too fatty already

-Removed FuncRef, since Callable makes it obsolete
-Removed int_types.h as its obsolete in c++11+
-Changed color names code

editor/plugins/sprite_frames_editor_plugin.cpp

@@ -30,8 +30,8 @@
 
 #include "sprite_frames_editor_plugin.h"
 
+#include "core/config/project_settings.h"
 #include "core/io/resource_loader.h"
-#include "core/project_settings.h"
 #include "editor/editor_scale.h"
 #include "editor/editor_settings.h"
 #include "scene/3d/sprite_3d.h"