OPENEDX_RELEASE doesn't work properly with variable inheritance in ansible
Merge pull request #1607 from edx/fix-openedx-release-vars

OPENEDX_RELEASE doesn't work properly with variable inheritance in ansible
Adding basic exemption
Add New settings to the env config.
Merge pull request #1609 from edx/e0d/notifier-vhost

Adding basic exemption
Correct the name of the ansible vars.
Merge pull request #1610 from edx/feanil/social_footer

Add New settings to the env config.
Create course data dir
Merge pull request #1611 from edx/create-course-data-dir

Create course data dir
Switch from legacy variable templating system to Jinja2 everywhere