Allow null as parameters in bulk delete method

wizard-server/src/main/java/org/cobbzilla/wizard/dao/AbstractCRUDDAO.java

@@ -355,14 +355,14 @@ public abstract class AbstractCRUDDAO<E extends Identifiable>
     }
 
     public int bulkDeleteWhere(@NonNull final String whereClause) {
-        return bulkDeleteWhere(whereClause, new HashMap<>());
+        return bulkDeleteWhere(whereClause, null);
     }
 
-    public int bulkDeleteWhere(@NonNull final String whereClause, @NonNull final Map<String, Object> parameters) {
+    public int bulkDeleteWhere(@NonNull final String whereClause, @Nullable final Map<String, Object> parameters) {
         final Session session = getHibernateTemplate().getSessionFactory().getCurrentSession();
         final String deleteSql = "DELETE FROM " + getEntityClass().getSimpleName() + " WHERE " + whereClause;
         final Query query = session.createQuery(deleteSql);
-        parameters.forEach(query::setParameter);
+        if (!empty(parameters)) parameters.forEach(query::setParameter);
         final int count = query.executeUpdate();
         session.setFlushMode(FlushMode.COMMIT);
         session.flush();