Add support for Warehouse

This depends on a few other fixes that need to happen:
- [x] Moving PyPI's Nginx configuration to be controlled by Chef
- [x] Fixing the issue where application_python fails to pip install because of a permission denied error
- [x] Moving dstufft/pypi.python.org to pypa/pypi.python.org
- [x] Upload PyPI secrets databag

However this provides the working of deploying Warehouse via Chef.