[poppler] pdftohtml: add version of poppler to the XML output

[Albert Astals Cid]

El Diumenge, 1 d'abril de 2012, a les 11:57:59, Ihar `Philips` Filipau va 
escriure:
> Add version to produced XML file.
> 
> In case somebody tries to change/improve the XML output format,
> version should at least give some guidance as to how parse the thing.
> Also, poppler's pdf2xml is pretty much only one which doesn't add some
> version information to the XML generated.
> 
> Patch attached.

This needs an update to the dtd too, doesn't it?

Albert