Merge pull request #288 from vcunat/vlada/gtk-renames

rename the expressions of some gtk-related libraries
add pangox-compat

It's needed for some packages to work with pango>1.30.*
gtkglext: fix by using pangox_compat
libvdpau: update
Merge branch 'master' into x-updates

Conflicts (both messed with mesa):
	pkgs/top-level/all-packages.nix
fix bad merge
Use libjpeg-turbo as the system-wide default.

ToDo: open an issue for discussion (testing, easy to revert).
Major Xfce refactoring, also adding versions 4.10.*

Please, comment on #296.
xfce: remove xfceutils from release.nix

It's no longer in Xfce.
fontconfig: propagation no longer needed
freetype+fontconfig: add infinality and enable it

Also add fontconfig checks
, change license to "unfree" if using patented code.

Inspired by Corey O'Connor in #89
https://github.com/coreyoconnor/nixpkgs/commit/27fec0aa26d44716134a86efaf48209be7c46138
cairo: bugfix update
gtk2: minor bugfix update
openjpeg: major update
fix the problem of missing expat in a few packages
Revert "openjpeg: major update": not good yet (mupdf)

This reverts commit b2a07ce1894ac8180cfe214ff65ac5ead328c065.
poppler: update; but openjpeg still not detected
openjpeg: use dependencies
libusb1: use pkgconfig
libmtp: update, minor fixes