Address https://issues.apache.org/bugzilla/show_bug.cgi?id=45255
Prevent session fixation by providing option (disabled by default) to change session ID on authentication
git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc5.5.x/trunk@918761 13f79535-47bb-0310-9956-ffa450edef68