Try to drop EndpointExposure

[philwebb]

It might be possible to drop the EndpointExposure enum and replace it with a class. Currently it's somewhat limiting in that additional items can't be added easily.

We might be able to use Class<? extends AnnotationEndpointDiscoverer>.

[philwebb]

The enum really reflects reality. For example, we need to generate *.jmx and *.web property meta-data. We probably shouldn't try to over complicate things.

[philwebb]

Actually, now the package restructure is in I would like to reconsider our options. Something doesn't feel quite right about EndpointExposure, especially as it's really only used to limit a couple of endpoints.

The jmx and web meta-data might also be worth a revisit. Enabling on a per technology basis is adding complexity. Perhaps we can just get away with a single enabled?