SSO now retains just the session ID rather than the actual session
object so there is no need to remove sessions that have been passivated.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1646717 13f79535-47bb-0310-9956-ffa450edef68
Comment typo

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1646718 13f79535-47bb-0310-9956-ffa450edef68
Should use containerLog rather than own log

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1646719 13f79535-47bb-0310-9956-ffa450edef68
Calls to associate need to trigger a Map update as well

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1646720 13f79535-47bb-0310-9956-ffa450edef68
Refactor to replace reverse map with dedicated session listener that
contains a reference to the SSO ID.
This refactoring is in support of the fix for BZ 57338.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1646721 13f79535-47bb-0310-9956-ffa450edef68
Refactor to use a serializable session listener to do the removal from
the SSO cache when the session expires.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1646722 13f79535-47bb-0310-9956-ffa450edef68
Debug logging improvements

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1646723 13f79535-47bb-0310-9956-ffa450edef68