feat: hook up ci to publish to npm

[george-haddad]

This pull request will set up mercury for publishing to npm

Publishing manually

1. cd to root directory of project
2. run npm login
3. run npm publish to publish package privately
4. run npm publish --access public to publish the package publicly

The way it is setup is that Circle CI will listen for a git tag event that follows the naming convention of v0.0.0 and that will trigger an npm publish.

The current config is set to publish the package publicly, so merging the PR should be fine and not trigger a publish until a git tag is created.

[george-haddad]

What's bugging me about this test is that it should be doing everything at UTC timezone offset. Which for this date would be '2017-01-09T03:00:00.000Z' and not '2017-01-09T05:00:00.000Z' when using .toISOString() which by default it does not preserve the original timezone offset.

But if I preserve the timezone offset as an ISO string it will include +02:00 which is my timezone offset from UTC. Clearly this is not portable around so I had to change the test to just check the date without the time + zone offset.

https://github.com/postlight/mercury-parser/blob/ae81557b75a5f1c9cb2efd260be04ab4f49ee9d0/src/extractors/custom/www.fastcompany.com/index.test.js#L55-L63

I think we should create a task to re-code all the date_published tests to be in pure ISO8601 without any timezone offsets, that way it can work anywhere.

[adampash]

I think we should create a task to re-code all the date_published tests to be in pure ISO8601 without any timezone offsets, that way it can work anywhere.

@george-haddad I think that's completely sensible. Do you want to make an issue out of it?

[adampash]

I've not done this before, but wouldn't bundleDependencies include all of the browser dependencies below?

[george-haddad]

I checked the node_modules directory of the package and it only included those 2 single packages. The test create-react-app won't start without them and this was the only way to get them bundled in the npm package.