RendererHints: accept function as well as closure
Convert GeoscalingDnsService to interface+impl

- AbstractGeoDnsService and GeoscalingDnsService
Convert MovableCloudFoundryClusterExample (to use interface+impl etc)

- Deletes MovableEntityTraitAlt
- Convert MovableEntityTrait from groovy to java
- Convert MovableElasticWebAppCluster to interface+impl
Convert hadoop-and-whirr examples (to use interface+impl)