Bootstrap ACL System From Web UI

### Proposal

After doing the manual ACL bootstrap process enough times, I think it'd be nice to be able to perform that action from the web UI as well. A rough idea of what I'm thinking that could look like:

### Use-cases

When a Nomad cluster is first provisioned with ACLs configured, a manual (or otherwise automated) ACL bootstrapping step is required. I often open up the UI first before running the bootstrap command, and would love to _not need_ to context switch back to my terminal right away. I imagine being able to perform this action from the UI will probably be most useful in getting started or demo environments, but would be nice to have.