Added an example for classification using iris dataset

[vickylance]

Hi,

I have created an example that does simple classification on the famous Iris dataset using the Toy nn lib by loading and parsing a csv file.

Please let me know if it is helpful :)

Thanks.

[shiffman]

This is great! At the moment, this is a "client-side" library only. I am not at all opposed to turning it into a node package or creating node examples, but what do you think about making a version of this that is client-side and uses p5's loadTable()?

[vickylance]

@shiffman Sure it shouldn't be much of a problem to put it into an index.html file. But also I think we can make the nn lib capable of running on both nodejs and web browser, simultaneously. Well that is how most of the npm packages work. We would only export it if module !== undefined . Nevertheless I will update once I make it into a html file