Write getting started guide

[acrosman]

Summary
This project really needs a better getting started guide as part of the repo itself.

Proposed Solution
I wrote one for my blog, but a version should really get folded in here.

• Update and re-write text as needed into an Markdown file.
• Put file into documentation directory.
• Copy images from blog to repo (or add new ones). I give permission to anyone who wants to copy them even though they are shifting licensing in the process.
• Link from current README and any other adjustments to tighten the README itself.