Merge lp://staging/~prakhar126/postorius/adding_dropdown_option into lp://staging/postorius

I'm finding some errors in the tests here (missing commas, for example). I'll see if they're things I can fix relatively quickly.

Here's the fixed code. There were a lot of syntax errors here. In future, please actually run the tests before you submit a merge proposal!

class ListNewTest(unittest.TestCase):

    def test_form_fields_list(self):
        form = ListNew({
            'listname': 'xyz',
            'mail_host': 'mailman.most-desirable.org',
            'list_owner': '<email address hidden>',
            'advertise': 'abcd',
            'description': 'The Most Desirable organization',
        })
        self.assertTrue(form.is_valid)

    def test_form_fields_list_invalid(self):
        form = ListNew({
             'listname': 'xy#z',
             'mail_host': 'mailman.most-desirable.org',
             'list_owner': 'mailman.most-desirable.org',
             'advertise': 'abcd',
             'description': 'The Most Desirable organization',
        })
        self.assertFalse(form.is_valid())