NAME
        Insert -- insert a node into a list

   SYNOPSIS
        Insert(list, node, listNode)
               A0    A1    A2

        void Insert(struct list *, struct node *, struct node *);

   FUNCTION
        Insert a node into a doubly linked list AFTER a given node
        position.  Insertion at the head of a list is possible by passing a
        zero value for listNode, though the addhead function is slightly
        faster for that special case.

   WARNING
        This function does not arbitrate for access to the list.  The
        calling task must be the owner of the involved list.

   INPUTS
        list - a pointer to the target list header
        node - the node to insert
        listNode - the node after which to insert

    SEE ALSO
        addhead(), addtail(), enqueue(), remhead(), remove(), remtail()