Fix: Issue #536

Following error condition triggers when there is None value for any DateField or DateTimeField. I.e. value == None

File "-/django_extensions/management/commands/dumpscript.py", line 718, in get_attribute_value
return "dateutil.parser.parse(\"%s\")" % value.isoformat()
AttributeError: 'NoneType' object has no attribute 'isoformat'

The proposed fix is to check the value against None before actually calling isoformat on the value.
Merge pull request #537 from Shanto/patch-1

Fix: Issue #536
Adding RUNSERVERPLUS_SERVER_ADDRESS_PORT to docs

The RUNSERVERPLUS_SERVER_ADDRESS_PORT is a handy shortcut and I couldn't find it documented anywhere except on the code.
Merge pull request #538 from leonsas/patch-1

Adding RUNSERVERPLUS_SERVER_ADDRESS_PORT to docs
small language fix
fix python3 support for configparser
v1.3.11
bumped version number
reorder imports
fix bug where custom declared integer primary keys fields where mistaken for serial type
ticket #541 use the same exit codes as (gnu) diff uses
removed duplicate list comprehension
update to 1.7c3
ticket #541 add a little documentation for exit codes on sqldiff
fix typo
Fixed `update_permissions` on django 1.7. Added a test.
Merge pull request #542 from AsymmetricVentures/test_update_permissions

Fixed `update_permissions` on django 1.7
Merge pull request #540 from APSL/master

Generate automatic Django Admin classes by providing an app name
add pypy
sqldiff: Remove MySQL workaround, causes more issues then it solves.

Remove MySQL workaround for "weird bug". The original bug cannot be
tracked down nor reproduced. However, the workaround code produces
real bugs when detecting varchar display size. Removing the workaround
produces better, more accurate results for MySQL in many real test
scenarios.

Fixes #532