code: private void handleSuccess(KeenCallback callback,
                                 KeenProject project,
                                 String eventCollection,
                                 Map<String, Object> event,
                                 Map<String, Object> keenProperties) {
          handleSuccess(callback);
          if (callback != null) {
              try {
                  if (callback instanceof KeenDetailedCallback){
                      ((KeenDetailedCallback)callback).onSuccess(project,
                                                                 eventCollection,
                                                                 event,
                                                                 keenProperties);
                  }
              } catch (Exception userException) {
                  // Do nothing. Issue #98
              }
          }
      }
docs: Reports success to a callback. If the callback is null, this is a no-op. Any exceptions
  thrown by the callback are silently ignored.
  
  @param callback A callback; may be null.
  @param project         The project in which the event was published. If a default project has been set
  on the client, this parameter may be null, in which case the default project
  was used.
  @param eventCollection The name of the collection in which the event was published
  @param event           A Map that consists of key/value pairs. Keen naming conventions apply (see
  docs). Nested Maps and lists are acceptable (and encouraged!).
  @param keenProperties  A Map that consists of key/value pairs to override default properties.
  ex: "timestamp" -&gt; Calendar.getInstance()