Dropped the DJANGO_TEST_TEMP_DIR environment variable.
Before this change, proper removal depended on the developer passing
dir=os.environ['DJANGO_TEST_TMP_DIR'] to tempfile functions.
The following are recognized as ending a line: the Unix end-of-line
convention '\n', the Windows convention '\r\n', and the old
Macintosh convention '\r'.
http://www.python.org/dev/peps/pep-0278
Thanks tchaumeny for review.
Added condition to prevent checking the existence of a file name of a
file like object when the name attribute is None. This is necessary
because a SpooledTemporaryFile won't exist on the file system or have a
name until it has reached its max_size. Also added tests.
Due to a mixup between text and bytes, iteration over
a File instance was broken under Python 3.
Thanks to trac user pdewacht for the report and patch.
Added comments in the three empty models.py files that are still needed.
Adjusted the test runner to add applications corresponding to test
labels to INSTALLED_APPS even when they don't have a models module.
- TemporaryFile now minimally mocks the API of the Python standard
library class tempfile.NamedTemporaryFile to avoid AttributeError
exceptions.
- The symbol django.core.files.NamedTemporaryFile is actually assigned
as a different class on different operating systems.
- The bug only occurred if Django is running on Windows, hence why it
was hard to diagnose.
