Integrated Submissions Pie Chart into Student Overview

Using HighCharts via the lazy_high_charts gem. Chart is created in the user_controller and displayed in the users/show.html.erb view.
Completed graph for Flesch-Kincaid Readability Score Over Time on the Student Overview page.

Graphs created in users_controller.rb and rendered in views/users/show.html.erb
Cleanup and decided to remove vocabularic complexity graph
Merge pull request #84 from whoisglover/student_overview_charts

Student overview charts