Modify umask set by mhshow to enable user execute bit, so that viewers that
[mmh] / zotnet /
drwxr-xr-x   ..
-rw-r--r-- 2780 Makefile.in
drwxr-xr-x - bboards
drwxr-xr-x - mf
drwxr-xr-x - mts
drwxr-xr-x - tws