[CM] bow in strad.ins

[Bob Coyne]

I tried the bow instrument in strad.ins and it gets
an divide by zero error in cmucl when I try playing it.
Is this instrument supposed to work? I've found various
others that also don't work and can send a list of them
if it would be useful.

Also, one other detail that should be covered in the
documentation/instructions. To load an instrument in cmucl,
you can't just say (load "<file>") because it will load the ".x86f"
binary file by default, and this doesn't work.  It's necessary, instead,
to do (load "<file>.cmucl").  I think this should be mentioned explicitly.