Merge pull request #782 from github/data-license

The _data is unrestricted, CC0-1.0

Author: mlinksva

readme.md

@@ -84,3 +84,9 @@ In addition to contributing changes, you can help to triage issues. This can inc
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 Don't see what you're looking for? Create an [issue](https://github.com/github/government.github.com/issues/new), we'll do our best to help you out.
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+## License
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+The data in `_data` is free to use without restriction. For clarity these files, and contributions to these files, are released under [CC0-1.0](https://creativecommons.org/publicdomain/zero/1.0/).
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+When using the GitHub logos, be sure to follow the [GitHub logo guidelines](https://github.com/logos).