The new client intro test mimics the Consul and Vault compat tests
and uses local agents to perform the required setup. This method
allows us the flexibility moving forward to test when enforcement
mode is in strict.
The test suite will now be triggered from the test-e2e CI run
and can also be called by a make target.
The e2e test code is absolutely hideous and leaks processes and files
on disk. NomadAgent seems useful, but the clientstate e2e tests are very
messy and slow. The last test "Corrupt" is probably the most useful as
it explicitly corrupts the state file whereas the other tests attempt to
reproduce steps thought to cause corruption in earlier releases of
Nomad.