MAKEFILE-ENVIRONMENT property is outdated #2756

There are bunch of files whose COMS explicitly establish a MAKEFILE-ENVIRONMENT property. I think this was the convention from an earlier time, before DEFINE-FILE-INFO was set up to store the property in the file hashtable.

There is a danger of confusion if these two specifications get out of step (as happened when I tried to convert POSTSCRIPTSTREAM to UTF-8).

It should be an error to make a file that defines this property--the property should be removed.