message: Add commentPreserveSpaces to readme
diff: @@ -134,6 +134,18 @@ They should be set via `Prettier`'s `overrides` option
  - `'as-needed'` -> Only add commas between attributes where required.
  Example: `button(type="submit", (click)="play()" disabled)`
  +- `commentPreserveSpaces`
  + Change behavior of spaces within comments.
  +
  + Choices:
  +
  + - `'keep-all'` -> Keep all spaces within comments.
  + Example: `// ___this _is __a __comment_`
  + - `'keep-leading'` -> Keep leading spaces within comments.
  + Example: `// ___this is a comment`
  + - `'trim-all'` -> Trim all spaces within comments.
  + Example: `// this is a comment`
  +
  The definitions for these options can be found in [src/options.ts](https://github.com/prettier/plugin-pug/blob/master/src/options.ts)
  ## Integration with editors
  