Final method2 implementation

Hcal 25ns reconstruction method2 implementation with fast fitter
Slava, the point is to pass the final state of the first Migrad fit to Scan, and then from Scan to Migrad to complete the cycle. If I do the Minimize separately independently, the results won’t be as good as the fits done in current way (effectively it’s just one fit anyway if they are independent). At least (to my best effort), I couldn’t find an easy way to use Minuit2Minimizer to get this done. Another point is that we can reduce the fits (maybe just one Migrad fit or something else smarter), but since in HCAL this method has been validated if we change anything drastically we’ll have to restart the validation...
> On Oct 31, 2014, at 4:56 PM, Slava Krutelyov <notifications@github.com> wrote:
> 
> In RecoLocalCalo/HcalRecAlgos/src/HybridMinimizer.cc:
> 
> > @@ -0,0 +1,969 @@
> > +// @(#)root/minuit2:$Id$
> > +// Author: L. Moneta Wed Oct 18 11:48:00 2006
> > +
> > +/**********************************************************************
> > + *                                                                    *
> 
> 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.
> 
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