Configure new JS client module and publish it on npm

[mbommerez]

Context:

w3name will be available as a public package

Scope of this ticket:

• Prepare module documentation
• Configure package.json
• Add license information, copy existing documentation in the readme file
• Publish package

Acceptance criteria:

• [ ] As a developer, I can install the w3name module with npm

[mbommerez]

We can start work on this, but let's not publish the package before:

• [ ] the API is deployed
• [ ] PL tech lead has reviewed the repo

[mbommerez]

This didn't need any code, just needed to publish it on NPM.

Outstanding:

• [ ] Add a warning that it's work in progress
• [ ] PR needs merging to make the tests pass and make the service optional
• [ ] Republish it (bumping the version number) as the published version isn't functional. It's dependant on the PROD API to be ready.