@Override
                    public void onTerminate() {
                        destroyed.set(true);
                        taskManager.terminate(taskContext.getTaskId());
                    }
Turn the {@link StatisticStoreDoc} into an {@link List<QueryField>} object
<p>
This builds the standard set of fields for a statistics store, which can
be filtered by the relevant statistics store instance
stroom-statistics/stroom-statistics-impl-sql/src/main/java/stroom/statistics/impl/sql/search/SqlStatisticSearchProvider.java