This directory contains the implementation of user session tracking and
processing functions.  When the source for a flow provides a TCP payload,
e.g. a socket connection, then the base Stream inspector delegates
handling of the packets on that flow to this module.

The StreamUser class is implemented as a subclass of Inspector and provides
functions for loading stream user configuration and packet evaluation.  The
packet eval method is not used as the base Stream Inspector delegates
packets directly to the user session packet processing method.

The User session module implements the following functions:

* Tracks the client and server side of the connection

* Manages list of TCP payload segments for reassembly into PDU  

* Initializes splitter for selected type of PAF

* Manages flushing the reassembled PDU

A UserSession object is allocated for each flow being tracked.  User
session state is maintained primarily in the UserTracker data structure
allocated for the client and server side of the connection. State
information includes:

* list of segments being reassembled

* PAF state

