Add Matt Campbell's proposal for a new protocol
Copied from @mwcampbell https://github.com/mwcampbell/ng-a11y, converted to reStructuredText, split single-line paragraphs into multiple lines.
Copied from @mwcampbell https://github.com/mwcampbell/ng-a11y, converted to reStructuredText, split single-line paragraphs into multiple lines.