[poppler] Poppler 0.18.0 released

[Albert Astals Cid]

Available from
http://poppler.freedesktop.org/poppler-0.18.0.tar.gz

Changes against the 0.17.4 release:
core:
 * Fix small memory leak when dealing with marked content
 * Remove DCTStream::getRawStream since Stream::getNextStream does the same
        
utils:
 * Rename pdfmerge to pdfunite
 * Rename pdfextract to pdfseparate
 * pdfseparate: Complain if %d is not present and it should
 * Add pdfseparate and pdfunite man pages
        
build system:
 * Minor cleanup in regarding removed qt code

Testing, patches and bug reports welcome.

I've also created the poppler-0.18 branch for fixes for the upcoming 0.18.x 
releases

Albert