ok, new libtool for cygwin updates

[edward]

the fix for pr19.test i posted is not intended to *fix* the test. rather, it
is meant for it to fail for the *same* reasons on any other platform that
uses gnu make, as opposed to failing because of a cygwin thing.

gnu make will remove intermediate targets, so make dist fails because foo.c
is an intermediary target that gnu make removes, but make dist expects it to
be there.

the cygwin portion failed because of a patch i made to automake, which broke
the 'make clean' target. however, the patch to automake is absolutely
crucial in order to get libtool to work correctly with dlls. in any case,
i've further patched automake to fix the things i broke.

hopefully, we can get this automake / libtool dependency thing worked out in
tandem.

thanks for looking into it,
edward