Merged requested to merge mjg/zathura-pdf-mupdf:mupdf-1.19 into develop
link against tesseract/leptonica for mupdf 1.19.0
Can be rebased easily, I was unsure about the appropriate target branch.
Fedora will ship an OCR-enabled mupdf soon. Although this will have no impact on the zathura plugin functionality (yet), the plugin need to be linked against tesseract/leptonica, too, so that all symbols of the mupdf library get resolved. This may be different once we switch to the dynamic mupdf library.