Add header component to NuxtJS Content project

We'll begin building the template by starting with the different main sections of the overall layout for our documentation site. We'll ultimately have a top header, a left nav / table of contents, and a main content section.

In this video, we'll create the beginnings of the top header.

Later on, we'll come back and make the header more mobile friendly as well as build out the search functionality.

In this video, I reference the following resources: