examples: Jaffle shop example added

[zilto]

This repository is a reimplementation of the canonical dbt example jaffle_shop. Here, Hamilton + Ibis provides a Python-centric alternative to dbt (Learn more). It illustrates data transformations for an ecommerce store. Since it is used by many different frameworks, it can ground comparisons between tools.

Changes

• added examples/jaffle-shop
• included data files

How I tested this

• ran run.py locally

Notes

• it servers as a good reference for tabular data workflows, but Hamilton supports a much wider set of use cases than dbt

Checklist

• PR has an informative and human-readable title (this will be pulled into the release notes)
• Changes are limited to a single goal (no scope creep)
• Code passed the pre-commit check & code is left cleaner/nicer than when first encountered.
• Any change in functionality is tested
• New functions are documented (with a description, list of inputs, and expected output)
• Placeholder code is flagged / future TODOs are captured in comments
• Project documentation has been updated if adding/changing functionality.

[skrawcz]

Looks good.

1. But question on location. Should this instead be under Ibis? Versus standalone jaffle-shop?
2. Where would a link in the main documentation help?
3. Would a vanilla pandas version be helpful?

[zilto]

1. But question on location. Should this instead be under Ibis? Versus standalone jaffle-shop?
2. Where would a link in the main documentation help?
3. Would a vanilla pandas version be helpful?

1. top-level jaffle-shop is a bit easier to find for those that know the name, but I agree to move it to Ibis given it's so tightly coupled.
2. I would include it in an upcoming docs/code-comparisons/dbt page. Hamilton and dbt might not be direct competitor, but it would give an idea to new users how concepts from translate to the other
3. it would be more work with little payoff IMHO given the goal is to showcase the "declarative orchestration" rather than "the data transforms". The code seems intelligible even if you don't know Ibis.

Other thoughts:
It would be cool to have a canonical Hamilton project (e.g., Ibis uses penguins dataset, dbt jaffle shop). It should serve the "Getting started" step-by-step tutorial, and be extensible to be able to showcase Hamilton features (add data validation, change execution engine, etc.). Will open an issue to spec this