Added proper tags

Tags are not a blob of strings anymore
Admin can enter tags more easily, beautiful and robust
This enables filtering, finding objects with similar tasks, etc. in
future updates

Also added many stylesheets etc. ( these came after "python manage.py
collectstatic" as per the setup instructions for taggit-autosuggest)
Merge branch 'tags'

Conflicts:
	codequiz-server/codequiz/settings.py
	codequiz-server/codequiz/urls.py
	codequiz-server/codequiz_db_file_2
	codequiz-server/quiz/models.py
	codequiz-server/quiz/templates/tasks/cq0_main.html
	codequiz-server/quiz/templates/tasks/cq1_task_meta.html
	codequiz-server/setup.py