message: docs(readme): add plugin section
diff: # :ocean: React Flow
  -React library for rendering an interactive node-based flow editor
  +React library for building node-based flow editors.
  # Installation
  @@ -29,3 +29,8 @@ npm install github:wbkd/react-flow
  - `backgroundType`: background type = `dots` or `lines`
  - `snapToGrid`: boolean
  - `snapGrid`: [x, y] array
  +
  +# Plugins
  +
  +- Mini map
  +- Controls: zoom & fit view
  