Modernize codebase: TypeScript migration 🙈 #186
Description
Codebase might seem quite outdated: vars instead of const/let, old way to define a class
It could be nice to modernize it. Currently, the package.json is telling us that we could use the library with at least Node 4. Therefore we can't just update the source code because we should keep it compatible with old Node versions.
I would suggest configuring Babel or TypeScript to be able to use the latest ES standard and stay compatible with the old node versions.