XyWrite 4 for Mac again

[Edward Mendelson <em36@xxxxxxxxxxxx>]

In order to avoid real work, I posted an updated version of this, with a 
prompt that tells where the XyWrite files are. Different download address:

http://www.columbia.edu/~em36/XyWrite4Mac.zip
Notice the http:// up there. If your browser says it can't find the 
file, that's because your browser insists on changing http to https. You 
can change it back.