Parameter ci of method TriplesPrivate::saveIndex not needed

[jmkeil]

I think, one could remove the parameter ci from TriplesPrivate::saveIndex as in the only implementation (BitmapTriples::saveIndex; TriplesList and TriplesListLong do not properly implement it) ControlInfo::clear will be called immediately. Therefore, it would be better to instantiate a new one in the method instead of manipulating a provided one.