Cygwin-64 fix

* bin/cygwin/epipe.pl: This is going to break when I go back to 32!
* etc/emacs/siscog/20configure-cygwin.el.pl: Idem
siscog hacks

* etc/acl/siscog/30siscog-tests.lisp: Set some vars, still not perfect, should be
some kind of ASDF hook.
* etc/emacs/common/50slime.el (require): Try to get rid of slime-space at least in
my local setup...