Issue #58: add halt/breakpoint handlers to ZnSingleThreadedServer>>serveConnectionOn: and ZnMultiThreadedServer>>executeRequestResponseLoopOn:
Issue #58: add ZnLogSupport>>object: ... for dropping an object into the object log...refactor REST tests to allow for testing using remote ZnGemServer and add persistence to ZnExampleStorageRestServerDelegate ... a bit of house cleaning in ZnGemServer