This fixes a weird issue where the following sequences of tests would fail:
test-backend
zerver.tests.test_messages.PersonalMessagesTest.test_personal_to_self
zerver.tests.test_report.TestReport.test_report_error
zerver.tests.test_templates.TemplateTestCase.test_custom_tos_template
It appears that all 3 tests are required for the failure.
While it's not entirely clear what the cause is, a very likely factor
is that settings.DEBUG is special, and so changing it at runtime is
likely to cause weird problems like this.
We fix this by replacing it with settings.DEVELOPMENT, which has the
same value in all environments, but doesn't have this problem of being
a special Django thing.
In python 3, subprocess uses bytes for input and output if
universal_newlines=False (the default). It uses str for input and
output if universal_newlines=True.
Since we mostly deal with strings, add universal_newlines=True to
subprocess.check_output.
For a long time, rest_dispatch has had this hack where we have to
create a copy of it in each views file using it, in order to directly
access the globals list in that file. This removes that hack, instead
making rest_dispatch just use Django's import_string to access the
target method to use.
[tweaked and reorganized from acrefoot's original branch in various
ways by tabbott]