Implementing Admin views

Implementing Users, Achievements and Feedbacks views.
Removed Profile admin views. Now the admin logic related to Users profile is handled by delegate method and nested attributes in Users edit view.
New layout created for admin views. Now the admin controllers extends the AdminApplicationController. This implementation is not definitive.
Fixed Achievement and Attempts Admin Controller tests.
Most of the admin controller tests working. 21 to go.
Started implementation of Integration Tests with Capybara.

Refactored controller_macros. Now the module is called "login_helpers", and includes 2 login methods to be used by controller and integration tests. The new login_with method was necessary because the Devise sign_in helpers are not avaliable inside the integration tests scope.
With whis, it was necessary do include in the spec_helper that the module is both a controller, request and feature module. For some reason, the before(:each) hook inside the login method stopped working. I removed it from inside the method and added in en each admin controller spec file. Now the tests are working again.
User show page now shows the achievements for that user.
All admin controller tests passing.
Starting conversion from Bootstrap 2 to Bootstrap 3

Replaced twitter-bootstrap gem by the official Bootstrap CSS and JS files, that are now in the vendor/assets folders.
Improvements in the Admin and Application Layouts.
Added Bootstrap 3 classes to all forms
Modifications in Layouts. Fixed the issue with the numbers in navbar. Started implementation of models methods.