[author] ZeroClipboard 1.2.0, 1.3.0, 1.3.1, and NPM auto-update.

This PR adds ZeroClipboard versions [1.2.0](https://github.com/zeroclipboard/zeroclipboard/releases/tag/v1.2.0), [1.3.0](https://github.com/zeroclipboard/zeroclipboard/releases/tag/v1.3.0), and [1.3.1](https://github.com/zeroclipboard/zeroclipboard/releases/tag/v1.3.1), as well as updating the associated "package.json" file to support auto-updating via NPM publishing in the future.

If you'd like separate PRs for those 4 things, just let me know and I'll be happy to accommodate. Thanks!

Associated issue: https://github.com/zeroclipboard/zeroclipboard/issues/284