fix: emergency fix

Merge github.com:Officeyutong/HelloJudge2 into master

fix: public problemset permissions

fix: app_name

improve: update README.md

improve: seperate frontend & new judger support

fix: clarification remove

merge: qbxtoj

fix: allow ioi contests

fix: syzoj-ng file downloading logic

fix: System Notification UID

fix: remove trumpscript

fix: error on manage.py

fix: issues when initializing db from scratch

feat: allowing toggle footer