updated home page for graduated ac to hide irrelevant information
added fix for notification email when ac does not have a coach
Merge pull request #80 from bsmith3541/coachNotificationBugFix

Coach notification bug fix
Add 'Decline invitation' link to users' feedbacks page
Restrict invitation decline permissions to admins/user who has been invited (with tests)
Add popup warning and sensible success message when invitation declined
Refactor table layout to take advantage of auto-formatting and (hopefully) be more extensible