[cvs-nhc98] patch applied (hat): Change some symbols in hat-detect and hat-observe:

Fri Feb 15 07:36:08 PST 2002 malcolm * Change some symbols in hat-detect and hat-observe: * <HIDDEN> becomes { } with a reverse-video box in the middle * <dummy> becomes {IO} in bold * <cut> becomes a reverse-video box M ./src/hattools/PrettyExp.hs -3 +4