Add some front page content

Tweaks 

- Copy edits for consistency
- Remove <br>'s for readability

Should all headers be Title Case? I see `Creating an App` but `Installing A Dependency`. I tend to use https://titlecaseconverter.com/, thoughts? 

Rename to match page "About The Docs"

These seem redundant, consider just "Getting Started"? Add more links?

Potpourri

Port user guide over

Add some headings to the getting started section

Add callouts and logo