Non-root Supervisor lands in 0.53.0, not 0.54.0
I _can_ count, honestly.
## Container Setup and Assumptions
When you run `hab pkg export docker`, you'll get a Docker container that provides a few things. First, a minimal Linux OS filesystem is provided, with just enough configuration (e.g., `/etc/passwd`, `/etc/resolv.conf`, etc.) to run. Second, the contents of the exported Habitat package, along with its complete dependency tree, as well as a complete Habitat Supervisor installation, are provided, unpacked, in the `/hab/pkgs` directory. Finally, an entrypoint script that will start the Supervisor, running the exported Habitat package, is provided, allowing the container itself to behave as though it were the Supervisor.
-On Linux, the Habitat Supervisor will normally run as the `root` user, and will start Habitat services as the `pkg_svc_user` specified by that service. However, in some deployment scenarios, it is not desirable (or perhaps even possible) to run the Supervisor as `root`. The [OpenShift](https://www.openshift.com/) container platform, for instance, does not run containers as `root` by default, but as randomly-chosen anonymous user IDs. From version 0.54.0 onward, the Habitat Supervisor can now run as an arbitrary user, providing users with more flexibility in how and where the use Habitat.
+On Linux, the Habitat Supervisor will normally run as the `root` user, and will start Habitat services as the `pkg_svc_user` specified by that service. However, in some deployment scenarios, it is not desirable (or perhaps even possible) to run the Supervisor as `root`. The [OpenShift](https://www.openshift.com/) container platform, for instance, does not run containers as `root` by default, but as randomly-chosen anonymous user IDs. From version 0.53.0 onward, the Habitat Supervisor can now run as an arbitrary user, providing users with more flexibility in how and where the use Habitat.
In order to support this in containers and provide maximal flexibility, the contents of the `/hab` directory are both readable _and writable_ by the `root` _group_. When specifying a user to run a container process as, the user's primary group will be reported as `root` if no matching group can be found in `/etc/group`. This will allow the user to create and populate the `/hab/sup` directory for managing Supervisor state, as well as the `/hab/svc` directory, which will contain all the service's state. This is in line with [recommendations from OpenShift](https://docs.openshift.com/container-platform/3.3/creating_images/guidelines.html#openshift-container-platform-specific-guidelines) on how to create containers that can run as a non-root user, but nothing in Habitat's implementation is specific to OpenShift; indeed, all the examples provided below use pure Docker.
