added uppo.py script

[Ali Gholami Rudi]

Hi all:

I've added contrib/uppo.py (short for update PO) script for making
updating translations a bit easier. It can be used like::

python uppo.py old_noor.po new_template_noor.pot output_noor.po

It imports the translation of the messages in ``old_noor.po`` to the
``output_noor.po`` if they appear in ``new_template_noor.pot``. The
encoding of the input files is assumed to be utf-8. Note that uppo
does not update the headers.

Hope it is useful.

Regards,
Ali

[zabeeh khan]

Great...