More exception handling
Merge branch 'feature/Reserves' into develop

* feature/Reserves:
  More exception handling
make reserves item_detail template inherit from icommons_ui/base_lti.html
changed login=true to login=yes in the iSites url
added the link to the digital materials if available; only display the HOLLIS link if there’s a HOLLIS id; HTML cleanup
small cleanup
continuing to improve form processing
modified add_user tool to use the new lti_role_required decorator (from django-auth-lti)
Merge branch 'feature/LectureVideo' into develop
continuing to improve form processing
Merge branch 'feature/student_locations' into develop
continuing to improve form processing
Merge branch 'feature/student_locations' into develop
continuing to improve form processing
Merge branch 'feature/student_locations' into develop
added new view main and moved contents of lti_launch into main. this is a fix for the authentication error that keeps occurring due to outdated post requests.
Merge branch 'feature/student_locations' into develop
Added new view main and  redirecting to this new method from  lti_launch. Changed the  lti_launch handler  to only accept the POST method. Also modified logic to get course instance id from the LTI_LAUNCH dict instead of request.POST.
Minor style change
fixed missing path variable. This must have been set because it passed through QA, but somehow vanished from the code. Weird.