Get donation link from package.json

[mappum]

Awesome project (and nice re-use of the name thanks)!

Now that it's getting so popular, it might be hard to scale the set of donation links since you would have to keep merging PRs every day. Instead, maybe it makes sense to also check packages for a donation field in their package.json, which would just contain the URL.

I'm not sure how you would do author links this way though.

[adrianheine]

Dupe of #2.

[feross]

@mappum Yep, you're right. This is already becoming an issue! Let's continue discussion in #2!