[PATCH] python: Add binding for notmuch_query_add_tag_exclude

[Justus Winter]

Quoting David Bremner (2014-09-20 07:15:02)
> Thibaut Horel <thibaut.horel at gmail.com> writes:
> 
> > Implemented as the method `exclude_tag` of the class `Query`. This method takes
> > one argument, a string containing the name of the tag to exclude
> 
> This tag looks pretty trivial.  I'll merge it unless I hear some
> objections over the weekend.

It looks fine indeed, thanks to the both of you.  The only tricky
thing I remember is the py2/py3 string/unicode thing, for which I seem
to have created the _str function, so it should be fine indeed.

Justus