Match FrVect with no name when reading with frameCPP
This PR updates the changes from #478 to match FrVects with no Name attribtue set - LIGO trend frames don't (currently) set the Name for FrVects, so need to pass empty strings.
This PR updates the changes from #478 to match FrVects with no Name attribtue set - LIGO trend frames don't (currently) set the Name for FrVects, so need to pass empty strings.