Proposal: market

[kkocdko]

Detail design draft:

• A json file placed in git repo. Open a pull request to add your extension into official market.
• The json file includes an array of links, the link is targeted to extension index.js. Don't include detail infos like description, because it will cause duplicates.
• Every day or week, use GitHub Actions to fetch info from links in JSON file, generate the full market index json.
• What about split into multi language?
• The generated full index json should be zipped then placed in GitHub Releases. It's filename may includes timestamp to get rid of the caching of unofficial GitHub Mirrors or GitHub's official CDN.