Honor `includeDefaults` in GeoPointFieldMapper.

Close #4563
move helper class for allocation tests to base class
mark abstract class as abstract
Expose filtered nodes on TransportClient
Expose the list of nodes that were filtered out with the TransportClient, for example, due to different cluster name. Relates to #4569
closes #4571
We run PluginManagerTests using only node client.

We also add some debug logs and fix `tests.network` (setting it to true was not working from jenkins)