Review of the Getting Started guide

[chrispine]

This update fixes typos, updates to more inclusive language, and adds clarity and structure to the Getting Stared guide.

Open questions before merging:

• Should we truncate long blocks of output? I noticed that sometimes we do and sometimes we don't, so wasn't sure what should be the default way of doing this.
• Is it okay to use the -auto-approve flag for this guide? Not having an interactive command is a bit smoother, but not necessarily better.
• I intentionally kept this CLI-only, and did not include using curl or the web UI. For a beginner resource, I thought it was better to provide one clear path to success.