enable ssl for nginx

By setting NGINX_ENABLE_SSL ssl this will be enabled in
the nginx configuration for those roles that support
it, currently just the lms and cms.

To use a custom key/cert set the following vars:

* NGINX_SSL_CERTIFICATE
* NGINX_SSL_KEY

Note that there is only one ssl certificate and key
per nginx install, this is because of the way nginx
is setup (independent of the other roles).

We could enable it for different roles though they would
share the same certificate.
defaulting SSL to False
enabling ssl for sandboxes, setting ssl port
Merge pull request #590 from edx/jarv/nginx-ssl

Jarv/nginx ssl
adding edx_ansible to continuous integration
by default enabling ssl in cont int
updating AMI to use the latest cont int image
removing enable ssl as a default
Merge pull request #592 from edx/jarv/add-edx-ansible-to-int

Jarv/add edx ansible to int
Lock the version of virtualenv.

The latest version of virtualenv install pip 1.5 which uses distlib which expects
a home directory where it can create a '.distlib' directory.

See: https://bitbucket.org/pypa/distlib/issue/39/using-distlib-with-pip-fails-when-usre-has
Explicitly set the npm registry.
adding vars for cert key files
changing instance type to small
updating ami for https support with valid cert
back to medium
Use npm config instead of editing rc files directly.
Merge pull request #605 from edx/jarv/add-star-cert

Jarv/add star cert
Merge pull request #603 from edx/feanil/lock_virtualenv

Feanil/lock virtualenv
adding course_data_path for ora
Merge pull request #608 from edx/jarv/ora-course-dir

adding course_data_path for ora