Ecaldqm harvesting migration

Migration of ECAL DQM harvesting modules under DQM/EcalMonitorClient and DQMOffline/Ecal. Passed standard DQM tests.
Automatically ported from CMSSW_7_2_X #5327
Sure, I think that is possible. It was using double because that's what ROOT THX binning specification uses, but so far there is no plan to generate ROOT histograms directly. Just out of curiosity, is this causing some bigger problem? Why do you care so much? This part of the code a histogram booking operation which is done at most (number-of-threads) x (number-of-run-transitions) times in a job.