Check key in JSX spread attribute (jsx-key)

[jomasti]

This looks for key in an object literal being spread into the component.

Closes #122

[palantirtech]

Thanks for your interest in palantir/tslint-react, @jomasti! Before we can accept your pull request, you need to sign our contributor license agreement - just visit https://cla.palantir.com/ and follow the instructions. Once you sign, I'll automatically update this pull request.

[adidahiya]

overall looks good. can you please enable CI by going to https://circleci.com/add-projects?

[jomasti]

I finally figured out how to get a build running for my branch. Shouldn't this project be set up to build PRs from forks, though? Anyway, the build fails due to Yarn not being able to find the binary for npm-run-all. It looks to be the same issue affecting the builds on master. From my quick research, it looks like the newer version of Yarn being used isn't compatible with the version of Node used by the container in CircleCI.

[adidahiya]

Good catch, I've fixed that on master here by migrating to CircleCI 2.0 #131

As a bonus, we also get testing of typescript@next. Can you pull in master to get the latest CI checks here?

[jomasti]

Awesome! Build is good now.