Add support for CoffeeScript triple backticks

[GeoffreyBooth]

CoffeeScript has a triple backtick operator now, to support JavaScript blocks without needing to escape the backticks inside:

time = ```function () {
  return `The time is ${new Date().toLocaleTimeString()}`;
}
```

[GeoffreyBooth]

Anything wrong with this?

[isagalaev]

Nothing wrong, just your regular open source maintainer with no time for the thing they maintain :-)
Thank you for the contribution!

[GeoffreyBooth]

Thanks!