Separate out notes into checks and action items

[RichardLitt]

The notes we currently have are not ideal. See shutterstock/juxtaposer#19:

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Dearest humans,

You are missing some important community files. I am adding them here for you!

Here are some things you should do manually before merging this Pull Request:

• Update the Contributing guide to include any repository-specific requests, or to point to a global Contributing document.
• Check the email in the Code of Conduct. We've added in "open-source@shutterstock.com".
• Check that nothing drastic happened in the package.json.
• Add some keywords to your package.json. We've added an empty keywords field for now.
• Check that the homepage in the package.json is OK. Another one besides your GitHub repo might work. We've set it to https://github.com/shutterstock/juxtaposer.
• If there are more contributors, add them to the Contributors field in the package.json.
• Add some tests! There aren't any currently set.
• Consider adding Travis. Travis is useful not only for tests, but also for greenkeeper and semantic-release.

Note: This pull request was automatically generated by https://github.com/mntnr/build-a-space. Found an issue? Let me know!

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"Update the guide" requires a check, but not necessarily any manual work. The same could be said of the CoC. However, "Add some keywords" requires manual work. Why don't you split these two types of notes up to make it easier to see what to do and what not to do.