Iterator all the things

* every object type implements HasId (can call getId():String).
* every container implements ContainerMeta<HasId>. This facilitates generic list calls in BaseClient.
* paints gson container and object classes with appropriate interfaces (they already implicitly implemented).
* adjustments to curator and archaius bindings.
* demonstates how to do this for ServiceClient
    * still needs to be done for ConfigurationClient and EventClient.
* using guava for iteration would have been overkill.