* Make each test file runnable using `module+'.
* Make the space tests not print anything (unless they fail, of course).
* Make the `first-class?' case even "more first class" by defining their
and/or as functions. (Doesn't make a real difference for this test,
but nice to test more of the language.)
The `or' and `and' functions already worked correctly; this
fix is for `or' and `and' as applied directly to arguments, which
expands to the `racket/base' `or' and `and' forms.
