It depends whether you want restarts handled from within your container or from the outside (e.g. orchestration framework).
With newer docker (1.2 onwards - https://docs.docker.com/engine/admin/host_integration/) you can have a container restart policy which handles a lot of the simple cases where previously one might have used supervisor.
Baking restart policy into the container can be convenient (and was considered standard practice before restart policies), but has the downside that it's a bit less flexible in terms of how your container works in different environments.
With newer docker (1.2 onwards - https://docs.docker.com/engine/admin/host_integration/) you can have a container restart policy which handles a lot of the simple cases where previously one might have used supervisor.
Baking restart policy into the container can be convenient (and was considered standard practice before restart policies), but has the downside that it's a bit less flexible in terms of how your container works in different environments.