BALL_UNION_SPHERE
        CBALL_DIFF_BALL
        CONNECTED_DIFF_BALL
        CONNECTED_DIFF_OPEN_FROM_CLOSED
        SPHERE_UNION_BALL

To address some licensing issues pointed out by Hendrik Tews,
made a couple of small changes to LICENSE/README files, and also
deleted pa_j_3.04.ml pa_j_3.06.ml.