- Fix the runner for Node.js v12 (which parses dynamic `import()` calls, but rejects the promise)
- Fix a Windows compat. issue in the test suite
- Wrap the content of `o.run()` callbacks in a try/catch block
- Add a `done()` callback to an async test
- Other minor superficial tweaks (remove typos and extraneous parens, move an array for convenience)