[Chicken-janitors] makefiles

[Elf]

i believe i have fixed the mingw, defaults.make, and rules.make files so that
make install will work properly.  cygwin is still being problematic, though;
ive gotten it to build successfully, but (use srfi-1), for example, errors about
being unable to load dynamic libraries.

i will upload the fixed files as soon as im back from the business trip.

-elf