updated .gitignore for .streamlit config folder

- added structure for multiple algorithm
- added Cross-Validation for SciKit Learn PLSR
- bases to add LWPLSR from Jchemo (Julia) - README.md updated
- added model export to disk
# Prediction
- working with Pinard prediction
- load models from disk
- export predicted values

added 2nd k-means to ensure random samples in a cluster are not close to each other in k-means sample selection