Add author field to Question and Answer models
Add user to QuestionCreateView

Add automatically put login user in author field in QuestionCreateView.
Add user to author.

Add login user to author field in AnswerCreateView.
Add author

Add author to question and answers.
Add UserFactory to author fields

Add UserFactory to author fields in QuestionFactory and AnswerFactory.
Merge branch 'author_fields' into develop

Add author field to Question and Answer models. The related CreateView saves the author field from the login user automatically. QuestionDetailView template display the authors of the question and answers. Added UserFactory to author field of related Factories.