pdftops: ensure paper size takes into account rotation

Bug 72312
pdftps: fix DocumentMedia/Page/Media/PageBBox DSC comments

Bug 72312
pdftops: Use crop box as page size

unless -nocrop is used. The fontends use the crop box as the page size and
acroread uses the cropbox as the page size for display and printing.

Bug 72312
pdftops: Remove origpagesizes mode and make -origpagesizes an alias for -paper match

Bug 72312
pdftops: Only change paper size when different to previous size

Previously this check was done in the code (removed in previous commit).
Moving this check into the pdfSetupPaper macro preserves page independence.

Bug 72312
pdftocairo: ensure page size and crop box works the same as pdftops

Bug 72312
cairo: clip to crop box

when printing the cairo surface may larger than the crop box

fixes https://bugzilla.gnome.org/show_bug.cgi?id=649886
pdftops: ensure there is always a page size in the output

even if the PDF file as badly broken.