Refactor

[mfeitoza]

@metonym from official Carbon Docs:

The UI shell is made up of three components: The header, the left panel, and the right panel. All three can be used independently, but the components were designed to work together.

So I refactored to use Header and SideNav independently.
Improve the StoryBook and organize the exports.

<Header bind:isSideNavOpen>
</Header>
<SideNav bind:isOpen={isSideNavOpen}>
</SideNav>
``

And also remove <footer> from SideNav, because I didn't found nothing in Carbon Docs.

[metonym]

Please resolve the import/export conflicts in src/index.js

[mfeitoza]

Done.

[metonym]

I like how the Storybook changes showcase the modularity of the UI Header, SideNav, and Switcher components.

Thanks again for taking the initiative with this refactor. I appreciate your focus on aligning the API with Carbon.

[metonym]

Released in v0.4.1