edx/edx-platform — pull request #2080 by olmar (2014-01-06 13:51:59+00:00)
Title: Add role parameter to LTI. BLD-583.

Add role parameter to LTI regarding IMS Global Learning Tools Interoperability™ Implementation Guide.

Issue: https://edx-wiki.atlassian.net/browse/BLD-583
Spec: Basic Launch Data http://www.imsglobal.org/LTI/v1p1p1/ltiIMGv1p1p1.html#_Toc330273026

@auraz and @nedbat please review.