Adding rds control libraries
Merge pull request #870 from edx/cg/extra-libraries

Adding rds control libraries
Added option to specify migration user and changed to admin user and password vars
Update to shibboleth role and allow changing the template directory
(cherry picked from commit ff86673d3a32e7a44f944f461135736708e08f81)
Updates to apache role to make it more flexible and inline with nginx
(cherry picked from commit b006e39b4e67226126649c5b9945cde8c41614a3)
Allows override of nginx configuration templates via simple variable
(cherry picked from commit be5948d91e7a88748a04fe37851b5a1bf6ce9e5c)