Use chartkick globally

* Clean up legacy charting imports
* Update existing donut and line charts
* Create helpers for parsing out existing chart data
* Move chart partials to a more common path

app/assets/javascripts/application.js

@@ -20,8 +20,9 @@
 //= require dataTables/bootstrap/3/jquery.dataTables.bootstrap
 //= require cocoon
 //= require bootstrap
+//= require Chart.bundle
+//= require chartkick
 //= require osem
-//= require osem-dashboard
 //= require jquery-smooth-scroll
 //= require trianglify
 //= require tinycolor