Documentation for Savitzky Golay filter

### Description

A proper discription for the usage of Savitzky Golay filter is missing in the official documentation. The example looks good, but usage, parameter description, and parameter usage should be explained. Use [1] and [2] as inspiration. [1] should be referenced in the docs. Requires knowledge regarding polynomial regression.

- Of course you can also start writing the tutorial/documentation in this issue/markdown files/scripts and afterwards we try to incorporate into the library.
### References

- [1] https://fslab.org/blog/posts/savitzky-golay-temperature.html#Savitzky-Golay-filter
- [2] https://github.com/fslaborg/FSharp.Stats/blob/8fb5d6dd07ff213a4e91b618fb2e654bc6147985/src/FSharp.Stats/Signal/Filtering.fs#L44-L61