edx/edx-platform — pull request #1637 by feanil (2013-11-08 20:48:35+00:00)
Title: Set empty aws credentials to None.

The way the ansible variable propagation is currently setup, we can't set the JSON values for AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY to None. If the string is empty it should default to None so that boto can attempt to use the instance IAM Role if possible.