Pixel cluster

Factor 2 speedup in SiPixelClusterProducer for HLT

1) small bug fixed in SiPixelGainCalibrationServiceBase
fixed for HLT and Offline
~0.01% of pixel were wrongly calibrated

improvements in
1) edmNew::DetSetVector (push_back(&&)
2) PixelDigi (faster and more useful sorting)
3) SiPixelGainCalibrationForHLT and SiPixelGainCalibrationForHLTService (added a getPedAndGain and a calibrate loop)
these improvements should be ported also Offline (for the time being a backward compatible implementation added)
and
4) PixelThresholdClusterizer use all the above + some cleanup

No regression observed

once also Sim and Reco are migrated a full cleanup of the interface would be useful...
I do not plan to work on that in the short term