Restructuring README.md

[schezfaz]

Fixes #397

Changes done:

• Created the following markdown files and added content:
  - ARCHITECTURE.md
  - SETUP.md
  - CODE_OF_CONDUCT.md
  - CONTRIBUTING.md
• Added hyperlinks to created markdown files from the README.md for ease of navigation

Preview Link(s): Please see the preview on this forked repository: https://github.com/schezfaz/Interactive-Book/tree/restructuring/%23397

✅️ By submitting this PR, I have verified the following

• Checked to see if a similar PR has already been opened 🤔️
• Reviewed the contributing guidelines 🔍️
• Sample preview link added (add the link(s) for all the pages changed/updated from the checks tab after checks complete)
• Tried Squashing the commits into one

[coding-CEO]

You should try to squash all commits to one.