added Array.last(), which returns last element in array
added a share schedule button.  when clicked, a modal pops up with a link to a scuclasses page that will show ONLY added sections.  when viewing this page, changes to the schedule are not saved to localstorage
fixes for things that were being hidden/shown incorrectly between normal/readonly versions
event tracking for share button clicks
reformatted ng-click attributes for top buttons, added print click track
got rid of inline print click tracking—already tracked in the controller
send number of sections added in ga event for schedule info and clear buttons
Merge branch 'feature/share_calendar' into develop