Display best test results for each difficulty level

[sheenaanto]

As a competitive user, I want my best results for each difficulty level to be displayed so that I can compare my progress.

Acceptance criteria:

• The best test result for each level is stored
• The best test result for each level is displayed on the site

Tasks:

• Create an area to display the best test results for each level of difficulty
• The best test result for each level is stored and displayed to the user