[asdf-devel] [bugfix] Fix ABCL loading ASDF definitions from jars under Windows

[Faré]

I realize that the following patch in needed in 1.713. Mark, can you
comment on whether it's always safe to use /___jar__root__file___/
without risk that a host/device will be imported from
default-pathname-defaults when I truenamize it?
-       (relativize-pathname-directory p)
+       (relativize-pathname-directory (ensure-directory-pathname p))

NB: So much for code freeze. While I was at it, I cleaned up
upgradability a bit, removed all warnings on ECL without triggering
them on Allegro, with declare ignorable, and added a trivial hook for
POIU, which I also upgraded (and it kind of works again with CLISP,
but not great). make test-all works for me on the listed
implementations. Here goes a Sunny Saturday down the drain...

[ François-René ÐVB Rideau | Reflection&Cybernethics | http://fare.tunes.org ]
A woman is not property, and husbands who think otherwise are living
in a dreamworld.
        — Robert Heinlein, "Time Enough For Love"