Fix link to documentation (or add project summary to README)

[coopr]

What does the code in this repo do?

The README includes "Documentation https://switchbox-data.github.io/smart-meter-analysis/ " - but that link 404s.

Please add a brief summary to the README of what this repo's code does - or fix the Documentation link? Thanks!

[linear]

SMA-42

[coopr]

Still would love to know what this code does!