Merge branch 'master' of git+ssh://metalzone.distorted.org.uk/~mdw/public-git/lisp

* 'master' of git+ssh://metalzone.distorted.org.uk/~mdw/public-git/lisp:
  asdf: Provide more package information and dependencies.
  sys-base: Only use the extensions package from CMUCL.
  base: Export unsigned-fixnum as a handy type to have.
  mop: Use CMUCL's `mop' package instead of `pcl'.
  base: New `until' macro does the obvious thing.