Core functionalities for libxfconf.

There is actually only one core function : xfconfListChannels. Access to the C functions xfconf_init() and xfconf_shutdown() are available in the System.XFCE.Xfconf.Unsafe module and should, in most cases, not be used in Haskell.

For more information, see: http://docs.xfce.org/api/xfconf/xfconf-xfconf.html