Add "node" to list of plugin in example

[laurent22]

The example is not quite complete as it doesn't mention that "node" should be added to the list of plugins (which I always forget to do).

[voxpelli]

eslint-plugin-n is the maintained version of this module.

We switched to it in eg. eslint-config-standard / standard and it is maintained by me and other members of the official ESLint community organization.

Try that module out and if it isn't fixed there, then open a new PR in that project.