Behavior of emp restart is confusing

[ejholmes]

Currently emp restart has the following behavior:

• emp restart will do a rolling restart of all processes. The implementation is weird since we perform a new release, when we should have a Restart method on the Scheduler interface.
• emp restart <ptype> returns an error InvalidParameterException: taskId shorter than 36.
• emp restart <ecs taskid> kills the ECS task.

With that said, the behavior we probably want is:

• emp restart to behave as above, but fix implementation details.
• emp restart <ptype> should do a rolling restart of the ECS service. Implementation should be pretty easy if we fix above.
• emp restart <ecs taskid> I'm not sure we actually want to keep this. It's almost never used and can be potentially dangerous since it doesn't do a rolling restart. This is actually really useful for stopping detached processes.

/cc @phobologic since you were talking about fixing this.

[phobologic]

Yeah, that's actually where I was thinking we'd go with this. I had the same concerns about the taskID method, then got pulled off on other stuff.