This PR removes enforcement that the Vault token role disallows orphaned
tokens and recommends orphaned tokens to simplify the
bootstrapping/upgrading of Nomad clusters. The requirement that Nomad's
Vault token never expire and be shared by all instances of Nomad servers
is not operationally friendly.
I apologize in advance for the rather long PR, but unfortunately there
is not an easy way to break this up into smaller chunks. This separates
the agent configuration into smaller, more consumable pieces just like
the job specification.