Add support to bind functions that make use of smart pointers (QPointer)

There is a set of method in IDentity class inside libsignon-qt[1] which has the following signature:

AuthSessionP Identity::createSession(const QString &methodName);
void Identity::destroySession(const AuthSessionP & session);

where AuthSessionP is defined as:

typedef QPointer<AuthSession> AuthSessionP;

Smart pointers are not yet properly handled by Shiboken, so at the moment this function cannot be used in the Python world.

This bug is a replay of the one that can be found at the old PySide bugtracker space at http://bugs.pyside.org/show_bug.cgi?id=1023

[1]
http://harmattan-dev.nokia.com/unstable/beta2/api_refs/showdoc.php?pkn=libsignon-qt&wb=daily-docs&url=Li94bWwvZGFpbHktZG9jcy9saWJzaWdub24tcXQ%3D