code: Instance createInstance(String name, Cls cls)
              throws KnowledgeSourceReadException {
          return getFromProtege(new InstanceSpec(name, cls), INSTANCE_CREATOR);
      }
docs: Creates a new instance in the knowledge base.
  
  @param name the name <code>String</code> of the instance.
  @param cls  the <code>Cls</code> of the instance.
  @return a new <code>Instance</code>, or <code>null</code> if an
  invalid class specification was provided.
  @see ConnectionManager#INSTANCE_CREATOR