Make logical pathname test work on disjoint files, for now.
Fix test-upgrade wrt recent package tweak in testing.

thanks to rpgoldman for detecting the typo.

The issue fixed is that most Lisps don't like
*default-pathname-defaults* being a logical-pathname.
Added a test for logical-pathname functionality;
it all works on CCL, and works better on other Lisps after the fix,
but there are still logical-pathname issues on SBCL, CLISP and more.
Also, a package cleanup of our test suite.