Add example Nomad jobspec for a Redis process.

Created by: smarnach

This adds a simple Redis jobspec, which is virtually identical to the Memcache jobspec. The main differences are naming and a count of 1 instead of 3 – as discussed on the ticket, we won't be able to use a highly available Redis deployment in this iteration.

This PR is not meant to be merged. We will add the ability to automatically launch the jobs to Ocim in a future PR, which will likely build on this jobspec, but put it in a Python dictionary rather than a separate file.

I started a job using this spec on the production Nomad cluster to verify the spec. Given that it is virtually identical to the Memcache spec, I don't think this needs separate end-to-end testing – simply sanity-checking the jobspec should be enough for review.