Added extra code to external class skeletons to reset 'out' parameters +...

Added extra code to external class skeletons to reset 'out' parameters + removed warning in generated code (bug 568899)

Signed-off-by: Botond Baranyi <botond.baranyi@ericsson.com>
Change-Id: I8c9ee720edd183711f709ad4c08629894747e1ed