docs(roundrobinlist.js): fix usage

[743v45]

push() returns the new length

const RRL = require('./lib/roundrobinlist');

const list = new RRL([1, 2, 3]);

console.log(list.next());
console.log(list.next(2));
console.log(list.next(2));
console.log(list.add(5));
console.log(list.next(2));

// [ 1 ]
// [ 2, 3 ]
// [ 1, 2 ]
// 4
// [ 3, 5 ]

[dudleycarr]

add returns the item added, not the length of the list.

nsqjs/lib/roundrobinlist.js

Line 37 in 457b2d5

* @return {*} The item added.

[743v45]

but add return push() not item.

[dudleycarr]

Good catch. The return value isn't used anywhere. That said, I think we should match the docstring instead of the current behavior.