new condition object (ZDC Low Gain Fraction) added for HCAL

new condition object named ZDC Low Gain Fraction was added for HCAL
You must now also get the HcalTopology object from the EventSetup and pass it via setTopo to your copy. The reason is if you get a HcalZDCLowGainFractions from the DB it will not have a topology object set.