demand view
Merge branch 'feature/demand-view'

Conflicts:
	webapp_python/active_learner.py
	webapp_python/static/js/router.js
	webapp_python/static/js/views/demand_classification_view.js
	webapp_python/templates/posts.jinja2
	webapp_python/templates/posts.json
	webapp_python/templates/uncertain_posts.json
	webapp_python/webapp.py
move prediction into posts
introduce navbar
introduce new overview view
overview view shows certain/uncertain posts