#23 DPI CALCULATOR

[Kostas Maistrelis]

thanks a lot for this wonderful project.

the motivation behind this patch is to add an dpi calulator
that calculates the dpi resolution from image dimension (pixels)
and the real dimensions of the original paper (cm)
i am using this patch because my original images are from camera
then there is not resolution information inside
i hope to find this usefull

the patch is for gscan2pdf version 2.6.5
file: bin/gscan2pdf
patch -p1 < 0001-add-dpi-calculator.patch