python: object converter: support named tuple
python: object converter: support named tuple

Change-Id: I8d5d93b3212ab38796c04403731caeb1071fcb79

vbarbaresi/libqi,aldebaran/libqi,bsautron/libqi,aldebaran/libqi-java,aldebaran/libqi,aldebaran/libqi,aldebaran/libqi-java,aldebaran/libqi-java