(no ticket) Specified django-extensions version in setup.py

Fixes this:

(virtualenv)accek@acksiazeczka deployment $ ./manage.py shell
Traceback (most recent call last):
  File "./manage.py", line 14, in <module>
    execute_from_command_line(sys.argv)
  File "/Users/accek/sio2-repos/virtualenv/lib/python2.7/site-packages/django/core/management/__init__.py", line 453, in execute_from_command_line
    utility.execute()
  File "/Users/accek/sio2-repos/virtualenv/lib/python2.7/site-packages/django/core/management/__init__.py", line 392, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/Users/accek/sio2-repos/virtualenv/lib/python2.7/site-packages/django/core/management/__init__.py", line 272, in fetch_command
    klass = load_command_class(app_name, subcommand)
  File "/Users/accek/sio2-repos/virtualenv/lib/python2.7/site-packages/django/core/management/__init__.py", line 77, in load_command_class
    module = import_module('%s.management.commands.%s' % (app_name, name))
  File "/Users/accek/sio2-repos/virtualenv/lib/python2.7/site-packages/django/utils/importlib.py", line 35, in import_module
    __import__(name)
  File "/Users/accek/sio2-repos/oioioi/oioioi/base/management/commands/shell.py", line 12, in <module>
    from django_extensions.management.shells import import_objects
ImportError: No module named shells

Change-Id: I5064b42113f01b7e139a9c43cf4b3d1370b34d23
Merge "(no ticket) Specified django-extensions version in setup.py"