When running the Fabio and Prometheus jobs for the metrics suite
it seems the outer directory is required in the call when
registering the job.
error: "e2e/input/fabio.nomad: no such file or directory"
Refactor the metrics end-to-end tests so they can be run with our e2e
test framework. Runs fabio/prometheus and a collection of jobs that
will cause metrics to be measured. We then query Prometheus to ensure
we're publishing those allocation metrics and some metrics from the
clients as well.
Includes adding a placeholder for running the same tests on Windows.
