Update to use the new fix for nonetypes.

CHANGELOG.md

+- Updated ansible fork with small bug fix.
+  - https://github.com/ansible/ansible/pull/10957
+
 - Role: edxapp
   - Removed post.txt from the list of files that will have its github urls replaced with git mirror urls.
 

requirements.txt

-git+https://github.com/edx/ansible.git@stable-1.9-plus-edx#egg=ansible==1.9.1-edx
+git+https://github.com/edx/ansible.git@stable-1.9-plus-edx#egg=ansible==1.9.1-edx.2
 PyYAML==3.11
 Jinja2==2.7.3
 MarkupSafe==0.23