* Get rid of the RCS Header stuff.  They're meaningless in git.
 * Add public domain comment to some of the files if the only comment
   was the RCS header.

lisp.c into the correct <foo>-os.h files.

versions of all the required things, this commit separates the
interrupt handler proper (now interrupt_handle_now_handler) from the
actual work-horse (interrupt_handle_now), which is now only ever called
from the two interrupt handlers, interrupt_handle_now_handler and
maybe_now_maybe_later.  This follows similar changes in SBCL, and is in
fact needed in order to properly use sigreturn in signal handlers, as
required to work around a problem with the G5.

preprocessor token.