Update README to new template

File is not updated as per the readme.md file template.

Drupal recommends the following README sections:

<ol>
  <li>Project name and introduction (required)</li>
  <li>Table of contents (optional)</li>
  <li>Requirements (required)</li>
  <li>Recommended modules (optional)</li>
  <li>Installation (required, unless a separate INSTALL.md is provided)</li>
  <li>Configuration (required)</li>
  <li>Troubleshooting & FAQ (optional)</li>
  <li>Maintainers (optional)</li>
</ol>