Revise pre-req's document

[elsevers]

At the 11/15/2023 meeting, the team came up with a plan for revising the eMach Pre-requisites document, as follows:

• Make approach 1 be the default approach (everyone should use virtual environments)
  • Approaches 2 and 3 can be acknowledged but not recommended (danger, monsters ahead) -- make this a sing collapsible section of alternate approaches
• Following this, we should have one section on virtual environments
• Create a new page for how to use VS Code with eMach
  • How to use interactive environments
  • Helpful extensions to install right away (see Nathan's recommendation here Pylance, Black Formatter, Ruff, Markdown All in One, markdownlink)
  • Difference between run vs debug
  • How to debug: break points, inspecting variables