Sync change of the get_cohorts function merged in get_cohort
Modify django_comment_client to use get_cohort with allow_multiple
No more need of course_id through the API, using project.course_id
Merge pull request #131 from aboudreault/cohorts-workgroup-group-project

Cohorts workgroup group project
Merge branch 'ziafazal/filter-course-users-by-orgs' of https://github.com/edx-solutions/edx-platform into ziafazal/filter-course-users-by-orgs