stabilize() --> lStable

        Performs incremental stabilization.  Each time this message is sent,
        some part of the stabilization process is performed.  Stabilization
        is performed in increments so that it can be interrupted by a
        keystroke or other asynchronous event.

        If the TBrowse object is already stable, a value of true (.T.) is
        returned.  Otherwise, a value of false (.F.) is returned indicating
        that further stabilization messages should be sent.  The browse is
        considered stable when all data has been retrieved and displayed, the
        data source has been repositioned to the record corresponding to the
        browse cursor, and the current cell has been highlighted.