When developing on devstack, it's useful to have a way to share source
trees between the host and the guest OS. The src directory is for this
sharing, so that working trees can be accessed inside the guest OS.

First we update ansible then we run the playbook for the devstack.

ECOM-2184

edX can only support the latest Open edX release, which is Cypress as of
this commit. This commit clears out all the cruft from old Open edX releases
that edX cannot support anyway.

- Added explicit values for variables that must be shared between ecommerce and edxapp
- Added ecommerce virtualenv bin directory to PATH for ecommerce user
- Using local Django settings (instead of production)
- Disabled static file compilation for devstack
- Allowing ecommerce version to be specified via environment variable

ECOM-2185

Allows deployment of the ecommerce worker, a Celery-based IDA for asynchronously handling ecommerce tasks. ECOM-2306.

Counterpart to the Vagrantfile for testing individual Ansible roles.

The wiki page [here](https://github.com/edx/configuration/wiki/edX-Developer-Stack#installing-the-edx-developer-stack) says that the minimum Vagrant version is 1.6.5, not 1.5.3.

syntax

Making version handling consistent

whitespace

removing unrelated change.

reverting quotes