osutil.c: include Python.h before the other headers
This is recommended by the Python documentation, since Python.h defines
some constants.
adding dir/bar
adding foo
dir/bar
foo
adding dir/bar_2
adding foo_2
dir/bar_2
foo_2
adding a
adding c
adding b
adding d
removing a
removing c
recording removal of a as rename to b (100% similar)