v1.9.4.4

v1.9.4.4

New features:

1. add new test test_fitting_fitresult.py for variosu expressions and their uncertainties
2. improve Ostap::Math::Integrator allowig to specify the absolute and rleative precisions
3. move hash_combine from local_hash.h to Ostap/Utils.h
4. improve Ostap::Math::Piecewise
5. add helper scale factor for the Breitt-Wigner function
6. replace ROOT.Math.erfc with math.erfc in smear-function

Backward incompatible:

Bug fixes:

1. minor fix in histos.py:smear