Remove last traces of GConf handling
    
    Fixes errors during gnome-games-extra package install:
    
    I/O warning : failed to load external entity "/etc/gconf/schemas/gtali.schemas"
    Failed to open `/etc/gconf/schemas/gtali.schemas': No such file or directory
    I/O warning : failed to load external entity "/etc/gconf/schemas/gnect.schemas"
    Failed to open `/etc/gconf/schemas/gnect.schemas': No such file or directory
    I/O warning : failed to load external entity "/etc/gconf/schemas/gnibbles.schemas"
    Failed to open `/etc/gconf/schemas/gnibbles.schemas': No such file or directory
    I/O warning : failed to load external entity "/etc/gconf/schemas/gnobots2.schemas"
    Failed to open `/etc/gconf/schemas/gnobots2.schemas': No such file or directory
    I/O warning : failed to load external entity "/etc/gconf/schemas/gnotski.schemas"
    Failed to open `/etc/gconf/schemas/gnotski.schemas': No such file or directory
    I/O warning : failed to load external entity "/etc/gconf/schemas/quadrapassel.schemas"
    Failed to open `/etc/gconf/schemas/quadrapassel.schemas': No such file or directory