Create monitoring-node-js-overview.md

[bnb]

Creates an overview file for Monitoring docs.

[sagirk]

@bnb monitoring-node-js-overview.md is currently placed in documentation/0000-template/. Not sure if that is where we still want it to go (?).

To be consistent with the rest of the content, would it be appropriate to create a new folder 0056-monitoring-node-js-overview, rename this file to index.md and move it there?

Also, the format for metadata at the top has changed in the newer handbook content. So, we may need to update that too.

[sagirk]

Metadata format example, as will be consumed by nodejs.dev:

---
title: An introduction to the npm package manager
description: 'A quick guide to npm, the powerful package manager key to the success of Node.js. In January 2017 over 350000 packages were reported being listed in the npm registry, making it the biggest single language code repository on Earth, and you can be sure there is a package for (almost!) everything.'
authors: flaviocopes
section: Getting Started
---

[keywordnew]

@sagirk I was about to merge this because it has enough reviews. I'm unclear on whether the later comment was meant to be blocking.

[Trott]

I've unarchived this repo so I can close all PRs and issues before re-archiving.