libspectre: minor update, patches no longer needed
minor poppler-data update
libtiff: major update to 4.*

Also minor modification of ghostscript to work with it.
freetype: minor update
harfbuzz: minor update
gobject-introspection: minor update
fontconfig: minor update
cairo: update, use xcb by default (no longer experimental)
djvulibre: minor update, refactored dependencies
glib: minor update

also needed for the updated cairo
gtk2: minor update
gdk-pixbuf: minor update