cruft at the end of bzip2 docstring

[Rik]

jwe,

If you try 'help bzip2' you'll see a bunch of cruft at the end of the
docstring which is the standard GPL file preamble.  The issue is in
libinterp/module.mk:

module.mk:      ( $(PERL) $(srcdir)/libinterp/gendoc.pl "$(srcdir)"
$(LIBINTERP_DEFUN_FILES); cat $(srcdir)/libinterp/op-kw-docs ) >
libinterp/DOCSTRINGS-t && \

Using 'cat' adds the entire file to DOCSTRINGS including the GPL preamble.

There is a note in op-kw-docs:

## FIXME: the information in this file is currently duplicated in help.cc.

Maybe an entirely different solution is desired given the FIXME note.  At
any rate, I thought I'd let you two know since you were working on this.

--Rik