feedback credit window
updated feedback notification to include info about credit window (when appropriate)
updated BFC validation to force credit window to fall within availability window; updated BFC display in LC
Merge remote-tracking branch 'upstream/master' into feedback_for_credit_window
ensured that feedback credit window does not extend before feedback availability begins
Merge pull request #199 from kevinburleigh75/feedback_for_credit_window

Feedback for credit window
added info on whether or not feedback has been viewed to Assignment page
fixed about styling
tweaked wording of feedback viewing status text
Merge pull request #203 from kevinburleigh75/student_feedback_credit_view

Assignment page exercise feedback view/credit info
segregated registered/auditing/dropped students in Assignment show page; added ability for instructors to toggle student dropped status
Merge remote-tracking branch 'upstream/master' into grader_display_updates
Merge pull request #204 from kevinburleigh75/grader_display_updates

Grader display updates
corrected bug caused by conflicting uses of instance variables; fixed sizing of new Exercise and RegistrationRequest dialogs
Merge pull request #205 from kevinburleigh75/popup_dialog_improvements

Popup dialog improvement
removed clearning of delays when not selected
fixed ordering in dev/admin toolboxes and Class roster pages to use case-insensitive ordering
added a Registration Status section to Class show page
removed double bar above "Status" section
Merge pull request #206 from kevinburleigh75/feedback_delay_saved_when_not_selected

Feedback delays saved even when not selected