gconf: new package

Signed-off-by: Joseph Kogut <joseph.kogut@gmail.com>
[Thomas:
 - propagate dependencies of selected packages in Config.in
 - add missing Config.in comment about dependencies
 - add missing upstream URL in Config.in
 - add missing comment header in .mk file
 - remove --disable-nls from configuration options, it is taken care
   of by the package infrastructure
 - remove --disable-dependency-tracking, it is taken care of in the
   package infrastructure
 - add $(TARGET_NLS_DEPENDENCIES) to <pkg>_DEPENDENCIES, since gconf
   has optional NLS support
 - add host-intltool to <pkg>_DEPENDENCIES, since gconf needs
   intltool-update
 - fix license: it's LGPL-2.0+, not GPL-2.0.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>