Splitting configuration into base class and some preprocessing adaptions
Summary
This MR introduces the following changes
- Splits the configuration into base class (needs to be also applied to training config later)
- Some preprocessing changes in docs and in configuration
- Speeding up scaling and shifting
- adding new option to preprocessing config
n_jets_scaling
which allows to use only a part of the jets to calculate scaling and shifting values - removing unnecessary variable loading into memory to get shape of jets
- adding new option to preprocessing config
Relates to the following issues
- first step towards #181 (closed)