Mark 3.1.0 (#1634)

# 3.1.0 / 2020-09-08

**General**

- Loosen team password confirmation in team settings to also accept the team captain's password to make it easier to change the team password
- Adds the ability to add custom user and team fields for registration/profile settings.
- Improve Notifications pubsub events system to use a subscriber per server instead of a subscriber per browser. This should improve the reliability of CTFd at higher load and make it easier to deploy the Notifications system

**Admin Panel**

- Add a comments functionality for admins to discuss challenges, users, teams, pages
- Adds a legal section in Configs where users can add a terms of service and privacy policy
- Add a Custom Fields section in Configs where admins can add/edit custom user/team fields
- Move user graphs into a modal for Admin Panel

**API**

- Add `/api/v1/comments` to manipulate and create comments

**Themes**

- Make scoreboard caching only cache the score table instead of the entire page. This is done by caching the specific template section. Refer to #1586, specifically the changes in `scoreboard.html`.
- Add rel=noopener to external links to prevent tab napping attacks
- Change the registration page to reference links to Terms of Service and Privacy Policy if specified in configuration

**Miscellaneous**

- Make team settings modal larger in the core theme
- Update tests in Github Actions to properly test under MySQL and Postgres
- Make gevent default in serve.py and add a `--disable-gevent` switch in serve.py
- Add `tenacity` library for retrying logic
- Add `pytest-sugar` for slightly prettier pytest output
- Add a `listen()` method to `CTFd.utils.events.EventManager` and `CTFd.utils.events.RedisEventManager`.
  - This method should implement subscription for a CTFd worker to whatever underlying notification system there is. This should be implemented with gevent or a background thread.
  - The `subscribe()` method (which used to implement the functionality of the new `listen()` function) now only handles passing notifications from CTFd to the browser. This should also be implemented with gevent or a background thread.

tests/api/v1/test_scoreboard.py

@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 
+from flask_caching import make_template_fragment_key
+
 from CTFd.cache import clear_standings
 from tests.helpers import (
     create_ctfd,
@@ -40,13 +42,19 @@ def test_scoreboard_is_cached():
             assert app.cache.get("view/api.scoreboard_scoreboard_detail")
 
             # Check scoreboard page
-            assert app.cache.get("view/scoreboard.listing") is None
+            assert (
+                app.cache.get(make_template_fragment_key("public_scoreboard_table"))
+                is None
+            )
             client.get("/scoreboard")
-            assert app.cache.get("view/scoreboard.listing")
+            assert app.cache.get(make_template_fragment_key("public_scoreboard_table"))
 
             # Empty standings and check that the cached data is gone
             clear_standings()
             assert app.cache.get("view/api.scoreboard_scoreboard_list") is None
             assert app.cache.get("view/api.scoreboard_scoreboard_detail") is None
-            assert app.cache.get("view/scoreboard.listing") is None
+            assert (
+                app.cache.get(make_template_fragment_key("public_scoreboard_table"))
+                is None
+            )
     destroy_ctfd(app)