Add average attempts coursewide to the Problem Results table on the Individual Learner Dashboard

[crathbun428]

User Story
As a course delivery team member, I want to see a new Average Attempts Coursewide column in the Problem Results table on the Individual Learner Dashboard, so that I can easily compare how many times every learner in the course attempted the problem versus how many times one individual learner attempted it.

Acceptance Criteria
Given I have access to the Individual Learner Dashboard
When I view the Problem Results table
Then I see a new Avg Attempts Coursewide column to the left of the Correct Attempts column
And the Correct Attempts and Incorrect Attempts columns are renamed to the Selected Learner Correct Attempts and Selected Learner Incorrect Attempts
And (if possible) Visually indicate when the Sum of the Selected Learner Correct Attempts and Selected Learner Incorrect Attempts is lower, equal to, or higher than Avg Attempts Coursewide