building header for cohort view
Add neat, bitters, and refills
Merge remote-tracking branch 'upstream/master' into background
Add class groups to student model
postioning and styling on header, new placeholder icons in images folder
Updat seed data and WIP: group filtering
Merge branch 'klovelacek-background'

Conflicts:
	app/views/home/index.html.erb
Update backbone router