refs https://github.com/TryGhost/Ghost/issues/8106, https://github.com/TryGhost/Ghost/issues/7429, requires https://github.com/TryGhost/Ghost/pull/8137
-Adds new "card" menus
- Navigation with keyboard in both axis.
- Search with keyboard in both menus.
- Adds a "+" Menu for cards
- Adds a "/" Menu for cards
- if the block has content and it becomes a markdown or HTML Embed card then the content is included into the card.
- Image and HR cards appear below the current section
- Adds new toolbar with both inline and block styling.
- Adds a new 'divider' card.
no issue
- as a separate project a number of Ghost-Admin components and files had been copied verbatim, these are no longer needed as the original components are available now that the editor is integrated
