Dead Link in README.md

[kkin1995]

Hi, there is a dead link in README.md for Differential Equations in Data Science "Python Tutorial".

It takes the user to an online jupyter notebook link with a 404 Error.

[krishpy99]

Should we remove it?

[LukeHaushalter]

Should be fixed with Pull Request #167

[clarecorthell]

Thanks for the catch everyone!