Final method2 implementation

Hcal 25ns reconstruction method2 implementation with fast fitter
From profiling I can see that the cost of making another instance of Minuit is pretty small.
So, if this 4-tries  minimization (5 calls to ::Minimize)  in each fit can as well be done with several instances. [The problem with TFitterMinuit is that it's  not thread safe]. So, local reimplementation of the Minuit2Minimizer is not practical.