point to canvas.icommons.harvard.edu for the canvas API
Merge branch 'feature/Reserves' into develop

* feature/Reserves:
  Removed hardcoded iSites link
Merge branch 'feature/Reserves' into develop

# By Colin Murtaugh (1) and Mysore, Sapna (1)
* feature/Reserves:
  Don’t show topic locator link if topic id is not set
  handle case where the course_instance is mapped to an iSite and an external site
added site_type = 'sites' check to the course_instance query
Merge branch 'feature/LectureVideo' into develop
checking if external_id exists before passing it to query