Support numerous Metal nodes from a single execution

[displague]

Users would benefit from this tool being able to manage a large set of Equinix Metal nodes from a single binary execution.

What does this look like?

We could configure multiple nodes through configuration or convention. Configuration could look like a yaml file that defines each node. Convention could look like a project-wide configuration where the username is {project_uuid} and the password is {device_uuid}:{metal_auth_token}.

There are many approaches we could take here. This issue is a stub for discussion.

[displague]

In conversation with @dlotterman, some tools have strong opinions about the IPMI port that is exposed which would make port a fragile method of addibg multitennant support.