Phase 1: conditionally hide prize ui for non-US users
Merge branch 'master' into conditionally_hide_prize_ui

Conflicts:
	app/views/api/user_hero.html.haml
	app/views/devise/registrations/new.html.haml
	app/views/home/index.html.haml
Merge pull request #217 from code-dot-org/conditionally_hide_prize_ui

Phase 1: conditionally hide prize ui for non-US users