Have the unit tests report errors from test.sh

Have the unit tests report errors from test.sh

The default behavior of test.sh was to suppress all output from
test/regress, and say nothing but OKAY or FAILED.  This wasn't so good
for getting bugs reported, since lots of people didn't know to set
TEST_OUTPUT_FILE, or re-run ./test/regress on its own.

Now, when you don't specify an output file for test.sh, it runs
regress with the --quiet option.  This option makes the unit tests
only print output on failure, which is what we probably wanted.