dLeyna-server now handles invalid types.

Previously, invalid types were not handled correctly which could lead
to crashes when processing invalid meta data or when an invalid type
is passed from applications, in the create container function for
example.

See https://github.com/01org/dleyna-renderer/issues/30 for more details

Signed-off-by: Mark Ryan <mark.d.ryan@intel.com>
[GUPnP] Output parameters could not be initialized on success.

Fix https://github.com/01org/dleyna-server/issues/49

Check output parameters (string & int) before use, even if the command succeed.

Signed-off-by: Ludovic Ferrandis <ludovic.ferrandis@intel.com>