The e2e/acl package has some nice helpers for tracking and cleaning up ACL
objects, but they are currently private. Export them so I can abuse them in
other e2e tests.
This adds a new ACL test suite to the e2e framework which includes
an initial test for ACL roles. The ACL test includes a helper to
track and clean created Nomad resources which keeps the test
cluster clean no matter if the test fails early or not.