v1.9.2.6

v1.9.2.6

New features:

1. change order of arguments for constructor of `Ostap::Math::QGaussian` and `Ostap::Models::QGaussian`
1. add set of helpful fnuctions into `Ostap/QMath.h`
1. improve QGaussiang model 
1. add 2D Tsallis distribution for pt versus rapidity (to be validated!)
1. add option to sort (default is True ) for Data-like objects 
1. remove unnesessary ~__del__` method for `WorkManager` 
1. add trivial filter `frame_prescale`
1. add options `prescale_signal` and `prescale_background` for TMVA and chopping 
1. add C++ progress bar 
1. improve tree_project and ds_project methods 
1. improve frame progress 
1. improve frame project  
1. add progress bar to `Ostap::Trees::add_branch` and `Ostap::HistoProject::projectX`
1. add progress bar to `Ostap::PyIterator`
1. tuning `frame_project`
1. tweak parallel_test_toys 
1. issue warning message for `AsymptorocError=True` for ROOT<(6,27), see [ROOT-PR-11282](https://github.com/root-project/root/pull/11282)

Backward incompatible:

Bug fixes:

1. fix typo in parallel_toys - Thanks Dima Pereima for reporting the problem
2. set of minor fixes
3. fix recenly intorduced bug in pyselectors
4. fix a typo in tmva.py