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/mono/utils/path_utils.cpp

@@ -30,10 +30,10 @@
 
 #include "path_utils.h"
 
+#include "core/config/project_settings.h"
 #include "core/os/dir_access.h"
 #include "core/os/file_access.h"
 #include "core/os/os.h"
-#include "core/project_settings.h"
 
 #ifdef WINDOWS_ENABLED
 #include <windows.h>