Feature store notebook examples

[KshitizLohia]

Description

1. Add a notebook demonstrating feature store quick-start
2. Add a notebook demonstrating feature store querying
3. Add a notebook demonstrating feature store using spark magic
4. Add a notebook demonstrating feature store schema evolution and schema enforcement

ipynb Notebooks

notebook demonstrating feature store quick-start
notebook demonstrating feature store using spark magic
notebook demonstrating schema evolution

HTML Notebooks

notebook demonstrating feature store quick-start
notebook demonstrating feature store using spark magic
notebook demonstrating schema evolution

[lvallad]

I've reviewed/revised the notebooks and attached them to include in this PR.
Authors need to update the TOCs to match the section titles,
TC Review.zip