Use globals npm package to set environments

This is a very simple approach that maintains parity with what was there before. In the future a slightly more programmatic solution could be undertaken to automatically expand the environment sets as they come in from the globals module.

Resolves #1577
sindresorhus/globals#4
No problem, but I'm sure you're aware that only a few of your existing source files carry a similar copyright notation. So I didn't recognize it was necessary by perusing the existing code.