Add regression models

Maintainer: [@prateekiiest](https://github.com/prateekiiest)

## DESCRIPTION

Add regression models to the repo just like classiification.

## EXPECTED OUTCOME

1. create a 'regression' folder inside Code-Sleep-Python.
2. add a requirement.txt file which will include all required pakages.
3. Add .py file or jupyter notebook of various regression models.


Please assign this to me.
