[barcode] streaming mode for pcl output

[Alessandro Rubini]

> The file pclfilter.py is an example that should go
> into the doc directory as mentioned in the documentation.

Ok.
 
> I do not know texinfo at all so my text is rather unformatted.
> I would have wanted a new paragraph starting with "Use case"
> but do not know how. Also the line "Article name..." should
> probably be formatted somehow.

Ok, I'll take a look.
 
> If you want me to, I would produce another patch with
> some spelling fixes in the documentation.

If there are errors to fix, please do. I'll pull all of your stuff in my
tree this night.

Hmm... what about using "git format-patch" instead? That would
automatically leave your name in the patch when I pull it with "git
am". Otherwise I have to do it by hand -- not a bit issue, but
this management of email is one of the winning point of git over
plain old patch.

Thanks a lot.

/alessandro