Don't generate complement if we've already got one.
Don't generate complement if we've already got one.

AmeBel/relex,linas/relex,AmeBel/relex,leungmanhin/relex,opencog/relex,leungmanhin/relex,opencog/relex,leungmanhin/relex,linas/relex,AmeBel/relex,linas/relex,opencog/relex