Feature 68 dashboard

This branch contains :

- a merge of current **benel/Tire-a-part/master** and **benel/Tire-a-part/feature-68-dashboard** with corrections of conflicts etc.

- **feature-68** test

- Modif of **templates/activity_html.html** :
  - add "Compter" button
  - click event on "Exporter" and "Compter" ( $('#id').on('click', function(){}) )

- Modif  of spec_helper.rb : 
   - Changed const **Capybara.default_wait_time** from 2s (default value) to 4s *RQ: minimum value = 3.5s*