Use official wunderlist node-module

[Thor77]

It seems like wunderlist provides an official supported node-module (since 03/2015) for easy api-access.
We should check if it provides all the features we need and maybe rewrite parts of Wunderline on top of it.

[wayneashleyberry]

Yeah, I seem to remember not using it for some reason... but it's definitely worth re-evaluating.