storage.models changed IO error message

e.g. "IOError: Media Error: file None could not be stored in Test"
instead of "Media file could not be stored"
storage.tests.py hacking

trying to figure out why the psueudostreaming test is failing - changed
a few test values and added a debugging print line
settings_test.DATABASES['NAME'] change

if I name the database 'mdid' it fails, if I name it 'test_mdid' it
creates a database called 'test_test_mdid' which lead me at some point
to name the database 'test_test_mdid' but when I got sick of seeing the
message "Destroying test database for alias 'default'
('test_test_test_mdid')..." so I'm going back to the middle ground.
fix error in data.tests.py

        # this test was throwing this error:
        # TypeError: can't subtract offset-naive and offset-aware
datetimes
        #  - I'm pretty sure this is a problem with the test not what's
being tested
        #  - dates created for records have timezones in them, so it
should be checked against a tz-aware now()
        # was:
        # self.assertEqual(True, datetime.now() - record.created <
timedelta(0, 120))
        # self.assertEqual(True, datetime.now() - record.modified <
timedelta(0, 120))