Logging

[dartvandru]

The Java client logs has the option of logging all important activity:
Search the code for all uses of this class:
https://github.com/eventuate-clients/eventuate-client-java/blob/master/eventuate-client-java-common-impl/src/main/java/io/eventuate/javaclient/commonimpl/EventuateActivity.java

That makes it possible to search the logs and see when an event was saved, processed by an event handler, whether an event handler succeeded or failed.