[docs] Update README to fit template and edit for clarity

Updates README structure to include template sections and TOC. Edits for clarity, flow, and additional information about exec params (for ease of use and to ensure information is available when access to the internet is not).
There is some trickiness here that you may want to call out. Typically single quotes and `$` are a bad thing in puppet since single quotes disable variable interpolation.

But in the `command` above, the `$` is part of the powershell script, so we have to prevent puppet from doing variable interpolation.