Extension for Lisp files

[Glenn S. Burke <GSB at MIT-ML>]

When we started transporting stuff written with LSB to SPEECH we just
punted the maclisp convention, because the stuff was lispm source compatible.
The LSB code, modulo a couple kludges like in the load function (which 
already does some checking), only really likes the LISP extension.
Personally i think Maclisp should be changed.