Documentation update

[Oliviu27]

When downloading and inserting your credentials.json, the credential's default key is "web".

At startup time this creates a failure because of the following line of code:

node-samples/slides/quickstart/index.js

Line 43 in 5b5cce7

const {client_secret, client_id, redirect_uris} = credentials.installed;

The suggestion is to update the docs with:
const {client_secret, client_id, redirect_uris} = credentials.web;
or alternatively, for the default key of the downloaded JSON to be installed rather than web.

I would assume updating the docs accordingly is easier.

[sqrrrl]

Quickstart guide + code was recently updated, marking as fixed.