Update BTag DQMOffline and Validation codes to match new ThreadedDQM fra...

...mework and cleaning.

Complete transition to the new DQM framework of the Btag modules and cleaning of the code.

Few things which could be discussed:

- I was not able to to update properly this function due to my lack of knowledge with "boost:bind":
https://github.com/acaudron/cmssw/compare/DQMHarvesterBTag#diff-9cad6096c5f7ae512cc862266f56a248L93
this function for the moment is not doing anything but perhaps some day it will be used. For the moment I just commented it and  it's probably fine for now.

- I let thread_unsafe the following class:
https://github.com/acaudron/cmssw/compare/DQMHarvesterBTag#diff-387724e025d75a5c1fc61796fd30b2f7L37
but I don't define this new class as thread_unsafe:
https://github.com/acaudron/cmssw/compare/DQMHarvesterBTag#diff-54c3cebbb4084fd4795f949811595b12R18
Is it fine?

Thanks for the help.