gnu: Add xfwm4.
* gnu/packages/xfce.scm (xfwm4): New variable.
gnu: Add thunar-volman.
* gnu/packages/xfce.scm (thunar-volman): New variable.
gnu: Add thunar.
* gnu/packages/xfce.scm (thunar): New variable.
gnu: Add xfce4-settings.
* gnu/packages/xfce.scm (xfce4-settings): New variable.
gnu: Add xfce4-session.
* gnu/packages/xfce.scm (xfce4-session): New variable.
gnu: Add xfce4-appfinder.
* gnu/packages/xfce.scm (xfce4-appfinder): New variable.
gnu: Add xfce4-panel.
* gnu/packages/xfce.scm (xfce4-panel): New variable.
gnu: Add tumbler.
* gnu/packages/xfce.scm (tumbler): New variable.
gnu: Add garcon.
* gnu/packages/xfce.scm (garcon): New variable.
gnu: Add exo.
* gnu/packages/xfce.scm (exo): New variable.
gnu: Add libxfce4ui.
* gnu/packages/xfce.scm (libxfce4ui): New variable.
gnu: Add xfconf.
* gnu/packages/xfce.scm (xfconf): New variable.
gnu: Add libxfce4util.
* gnu/packages/xfce.scm (libxfce4util): New variable.
gnu: Add gtk-xfce-engine.
* gnu/packages/xfce.scm: New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.
gnu: freeipmi: Update to 1.4.7.
* gnu/packages/freeipmi.scm (freeipmi): Update to 1.4.7.
gnu: wget: Update to 1.16.1.
* gnu/packages/wget.scm (wget): Update to 1.16.1.
gnu: gdk-pixbuf: Propagate glib and libpng.
* gnu/packages/gtk.scm (gdk-pixbuf): Move glib and libpng to
'propagated-inputs'.
gnu: libxcomposite: Propagate inputs.
* gnu/packages/xorg.scm (libxcomposite): Move all existing 'inputs'
to 'propagated-inputs'.
gnu: Add cffi.
* gnu/packages/python.scm (python-cffi, python2-cffi): New variables.