s4:w32err_code.py script - put it under "scripting/bin"

I think this is a better location for this script. Since the subdirectory
"script" of "source4" contains only scripts for "make install" and "make
uninstall".

diff --git a/source4/script/w32err_code.py b/source4/scripting/bin/w32err_code.py
similarity index 100%
rename from source4/script/w32err_code.py
rename to source4/scripting/bin/w32err_code.py