What: Update the WG README

[TheFoxAtWork]

Why:

• Current README is out of date and missing key information

This change address the need by:

• Merging previous documentation into the README
• adding Objective of the WG
• defining Scope considerations
• adding Current Work
• listing previously known related groups

This PR resolves Issue #4

[mihaimaruseac]

One week passed with no additional comments, so this is ready to merge.

Thank you very much for the PR!