Pierre-Yves David <pierre-yves.david@logilab.fr> [Tue, 25 Jun 2013 19:50:16 +0200] rev 9096
[ClientConnection] directly use the Connection object to access the database
Now that Connection are a full featured standalone object we can directly
reference and use it in the ClientConnection instead of using the session.
The session object is kept around for a while to perform various utility role.