Merge branch 'core-updates'

gnu: xpdf: Use gs-fonts to provide standard postscript fonts.

* gnu/packages/pdf (xpdf): Add path to gs-fonts in xpdfrc.

Merge branch 'xorg' into core-updates

gnu: Add xpdf.

* gnu/packages/pdf.scm (xpdf): New variable.
* gnu/packages/patches/xpdf-constchar.patch: New file.
* Makefile.am (dist_patch_DATA): Add it.

gnu: add dependencies to poppler.

Add libpng and zlib to the inputs.

gnu: Rename module 'freetype' to the more general 'fontutils'.

* gnu/packages/freetype.scm: Rename file to...
* gnu/packages/fontutils.scm: ...this.
* Makefile.am (MODULES): Rename module.
* gnu/packages/{ghostscript,grub,pdf,texlive}.scm: Rename dependency.

gnu: Add poppler.

* gnu/packages/pdf.scm: New file.
* Makefile.am (MODULES): Add it.