wn_boxset -- set box drawing character set

        USAGE

          wn_boxset(ul, ur, tb, sd, ll, lr);
          int ul, ur, tb, sd, ll, lr;

            ul - upper left corner character
            ur - upper right corner character
            tb - top/bottom line character
            sd - left/right side character
            ll - lower left corner character
            lr - lower right corner character

          wn_boxset set the characters to be used to frame all future
          windows.

        RETURNS

          Nothing.

        CAUTIONS

          None.