Support command shorthands

[bart1024]

It's a common practice for a CLI tool to support shorthands, e.g. kubectl get services is the same as kubectl get svc, nats context is the same as nats ctx and so on.

It'd be nice for zed to support shorthands as well, so zed permission can be just zed perm for example.

[jzelinskie]

I think this is as simple as filling out the Alias field in the corresponding cobra.Command. Seems like a great first issue (once all the shorthand names have been bikeshedded 🤣)