Respond to comments:

Rename `TagRequiresBackend` to `TagRequiresSimulator`.
Eliminate Java `RequiresBackend` annotation - the ScalaTest `TagRequiresSimulator` tag may be used with either specification checks (via the `taggedAs (TagRequiresSimulator)`, or property checks (by passing it as an additional argument to the property). Examples of both are included in tests.
Update all tests requiring a simulator with the `TagRequiresSimulator` tag.