Includes:
* changes `nomad alloc status` and `nomad node status`
* changes to `volume` block in jobspec
* new `csi_plugin` block in jobspec
* new `nomad volume register/deregister/status` commands
* new `nomad plugin status` command
We mistakenly reference `CONSUL_TOKEN` where we should be using `CONSUL_HTTP_TOKEN`.
There is one case where `CONSUL_TOKEN` is correct - client.mdx there is a list of
default filtered environment variables, which for legacy reasons `CONSUL_TOKEN` will
always be one.
