fully qualify paths used for gsettings binary

Paths aren't qualified in the exec used to check or set gsettings keys, which leads to the following error:

    err: Failed to apply catalog: Parameter unless failed on Exec[set focus-mode on user amoe to 'sloppy']: 'gsettings get org.gnome.desktop.wm.preferences focus-mode | grep -q "'sloppy'"' is not qualified and no path was specified. Please qualify the command or specify a path.

This just qualifies the paths used for the gsettings commands so that they succeed.

The same might also need to be done for the `gconf` define, although I have not done that change.

Commit assumes gsettings is in `/usr/bin`.  The `gconf` define already assumes this path in places, so I figured this was fine.