finished implementing lesson - invite.
Merge branch 'develop' of https://github.com/lergo/lergo-ui into develop

Conflicts:
	app/scripts/controllers/lessons/StepDisplay.js
	app/views/lessons/index.html

Merge branch 'develop' of https://github.com/lergo/lergo-ri into develop

Conflicts:
	backend/ApiActions/UsersActions.js
	backend/controllers/QuestionsController.js
Merge branch 'develop' of https://github.com/lergo/lergo-ui into develop

Conflicts:
	app/scripts/controllers/lessons/StepDisplay.js
	app/views/lessons/index.html

Merge branch 'develop' of https://github.com/lergo/lergo-ri into develop

Conflicts:
	backend/ApiActions/UsersActions.js
	backend/controllers/QuestionsController.js