If wait was set to a longer time then session timeout, the session would be timeout even though there were connections waiting for a response. Did some refactoring so that the session "knows" when all connections are closed and now returns the current time if there are currently connections actively awaiting a response when requested to return the last activity on a connection.

git-svn-id: http://svn.igniterealtime.org/svn/repos/wildfire/trunk@6874 b35dd754-fafc-0310-a699-88a17e54d16e