[MINOR] swapped the queued and active sessions in the logs

[MINOR] swapped the queued and active sessions in the logs

It was not natural to read sess/pend/lsess/psess in the logs, so before
the feature became official, I've swapped them to read :

   pend/sess/lsess/psess

Where <pend> is the overall number of pending connections on this instance,
including all the servers queues, <sess> is the number of sessions remaining
active on the server when the log was emitted (after the end of the session,
or after parsing the request), <lsess> and <psess> are the number of active
sessions on the listener and on the process respectively.