Rename docs/index.md to docs/README.md

[gfscott]

WHY are these changes introduced?

Since the primary context for consuming this content is directly browsing GitHub, if we change this filename to README.md, it will display the page content when browsing this directory. That doesn't happen for index.md files, so you'd need to click through to actually see the table of contents.

Type of change

• Patch: Bug (non-breaking change which fixes an issue)
• Minor: New feature (non-breaking change which adds functionality)
• Major: Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

• I have added a changelog entry, prefixed by the type of change noted above
• I have added/updated tests for this change
• I have documented new APIs/updated the documentation for modified APIs (for public APIs)

[paulomarg]

I have no problems with this, but we may need to change the /README.md file to point here instead of index.

[thecodepixi]

You beat me to it! I just noticed this while working on my other docs PR. Ditto Paulo's comment about changing the link in the main README though.

[paulomarg]

🚢