[new feature] AttachPicture action

Hi,

The attached diff implements a new action called "AttachPicture", which
allows to add picture files (like AttachFile) but automatically reduces
the size of the picture in order to present it in a smaller format on the
wiki ("medium size" and "full size" are available as links). Resizing is
done within Python using python-imaging (aka PIL); the full, medium and
small size versions are all cached similarly to the way attachment are
stored (but in a different directory structure).

MoinMoin/action/AttachPicture.py is a modified version of AttachFile.py;
other changes were made by grep'ing on "attachment". This introduces a new
'picture:' tag, which may be redundant?

Attached diff file is against CVS. Feedback welcome, I'm no Python coder.
I imagine this could all be done from within AttachFile somehow..

S.

-- 
Mayotte - http://stephane.alnet.free.fr/