Add avatar binding to index html.
Hide challenge section when 'challenge object' does not exists
Add method to load challenge objects.
Remove '%s about how many users selected each answer' from non 'single response multiple choice'.
Add images versions constants.
Change 'History' text by 'Your progress' (dashboard).
Change 'get your score prediction' button color.
Merge pull request #58 from joanrm20/master

Maua client new features