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

modules/visual_script/visual_script.cpp

@@ -30,9 +30,9 @@
 
 #include "visual_script.h"
 
+#include "core/config/project_settings.h"
 #include "core/core_string_names.h"
 #include "core/os/os.h"
-#include "core/project_settings.h"
 #include "scene/main/node.h"
 #include "visual_script_nodes.h"