Merge pull request #1 from Wiki616/master

frontend
Merge pull request #7 from Wiki616/dev

Dev
remove unexpected folder
Merge pull request #12 from juniwang/master

remove unexpected folder
Merge remote-tracking branch 'upstream/master' into dev
update hackathon iframe url and add a radio
11
Merge remote-tracking branch 'upstream/dev' into dev

Conflicts:
	osslab/src/app/routes.py
	osslab/src/app/static/css/hackathon.css
	osslab/src/app/static/js/course.js
	osslab/src/app/templates/third.html
	osslab/src/app/views.py
Merge remote-tracking branch 'upstream/dev' into dev

Conflicts:
	osslab/src/app/models.py
update login
provide database implementation
qq login refactoring
Merge remote-tracking branch 'opentech/dev' into dev
implement github oauth login
Merge pull request #40 from juniwang/dev

implement DB and login