add option for a max buffer size

Add an option to set a max buffer size that will send an `error` event if `byline` has buffered a more than `maxBuffer` and still hasn't seen a `newline`
Yes. see line 104 (`this._lineBuffer = this._lineBuffer.concat(lines);`). That being said; at this point there should only be one element in `_lineBuffer` since the rest of the elements were removed and pushed in the while loop above.