Improve license resolution

Hey, 👋

License is not always shown, even if it's specified. Example:

https://nicedoc.io/substack/stream-handbook
https://github.com/substack/stream-handbook/blob/master/LICENSE

It would be also great to see a license if it's specified in package.json file (example) or even in readme (example).

Hey,

I agree with you but I'm not sure how to do that in a generic way.

Think this repository is oriented for any repository, not only npm packages!

Currently, the license is obtained from SPDX coming from GitHub API:

nicedoc.io/core/github/fetch-meta.js

Line 23 in 83c23fb

const license = get(info, 'license.spdx_id')

I did not find how GitHub determined it, but I feel that, if the field is missing, then the repository does not have enough information to determine it.

So my point is probably a better solution is to warn about that, more oriented to give users insights about missings things and how to fix them (see #67).

Yep, I saw that issue.

However, there are so many packages which don't use license file. In most of my packages there is a license info in package.json and in readme, but they will be considered as non-license and give a warning in this case (I kinda dislike creating separate useless file for license when it's already mentioned in 2 places) 🤔