OSS-E1466-Refactor grades_constroller on Expertiza

What our team has done:
Modify calculate_all_penalties method which is too complex and long.
Put the get_body_text method in a mailer rather than in the grades_controller.
Refactor conflict_nofication method to conflict_email and make it delegated to the mailer.
Refactor view_my_scores method to grades_show and delete the unnecessary variables.
Refactored get_assessments_for method in response_map.rb and lead to more than 90% off the current waiting time.
Try not to query for reviews and meta reviews in grades_show method.