Iteration with `[...new LineBreaker('...')]` etc

[lionel-rowe]

A useful convenience would be adding a *[Symbol.iterator]() method for a friendlier and more idiomatic API compared to the current nextBreak-based one.

console.log([...new LineBreaker('...')]); // [{ position: 3, required: false, substring: '...' }]

for (const bk of new LineBreaker('...')) {
  console.log(bk); // { position: 3, required: false, substring: '...' }
}