Fix some comments from permissions rework

Whoops, forgot to squash this in before pushing.

tildes/alembic/versions/84dc19f6e876_rename_column_for_restricted_posting_.py

@@ -1,4 +1,4 @@
-"""Rename column for restricted-posting groups
+"""Rename column for restricted-posting groups and wiki permission
 
 Revision ID: 84dc19f6e876
 Revises: 054aaef690cd

tildes/tests/test_user.py

@@ -155,7 +155,7 @@ def test_banned_user_no_message_permission():
 
 
 def test_ban_permission_manually_granted():
-    """Ensure it requires manually granting ban permissions."""
+    """Ensure ban permissions must be granted manually."""
     user = User("Test_User", "password")
 
     principals = principals_allowed_by_permission(user, "ban")

tildes/tildes/typing.py

@@ -1,4 +1,4 @@
-# Copyright (c) 2018 Tildes contributors <code@tildes.net>
+# Copyright (c) 2020 Tildes contributors <code@tildes.net>
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
 """Custom type aliases to use in type annotations."""