Radiobuttons do not allow to choose a unique option

[enricmartos]

Description

Radiobuttons do not allow to choose a unique option. This issue affects the sign up form (when the user has to choose his role as student or as a teacher) and the questions of the quizes for each lesson.

Steps to reproduce

• Go to the Sign Up form of the app
• Choose "Student" as a role. After that, if you select "Teacher" option, the previous selected option remains marked.

Actual result Radiobuttons do not allow to choose a unique option.

Expected result Radiobuttons should allow to choose a unique option.

[enricmartos]

The solution consists of assigning the same "name" attribute for all the radio buttons and add different "value" attributes for each one of them. Thanks to that, the post controller can parse the user input properly. So, now the user is no longer able to choose multiple options, just one, and he can switch frome one to another easily.