Include advanced data handling in workflow
Include all developments from #140 (closed), #141 (closed), #142 (closed), #143 (closed) into run_modules
- replace distributor by KerasIterator
- replace generator by DataCollection
- replace preparation by StationPrep + DataPrepration
- adjust data transformation
- adjust check stations
- all kwargs of StationPrep need to be implemented explicitly (like start, end)