[poppler] Trying to extend pdftoppm to use CairoOutputDev

[Adrian Johnson]

Albert Astals Cid wrote:
> I'm not really sure the use case is really that useful for the general public 
> to really include this in poppler utils, anyway there is a lot of cairo 
> specific code that needs to be properly ifdefed because cairo is an optional 
> dependency.
> 
> Also i think this belongs more into a separate binary than in the pdftoppm 
> one. We already "bastardized" it adding png and jpeg, maybe we should rename 
> it to pdfconvert or something like that.

I have a pdftocairo util that I use for testing. This may be a better 
way of exposing the cairo png/ps/pdf output.

http://people.freedesktop.org/~ajohnson/0001-Add-pdftocairo-util.patch