Add Category and Author meta links to Posts and Post Carousel block output

For the best blocks plugin out there, I would like to see in both posts blocks, the ability to show the parent category and the author meta links, toggled to appear next to the date output, each separated by a dot!

For other projects, with a different blocks plugin, which I think uses older methods with much more php, I've used a separate [categories.js](https://gist.github.com/broken8/d03258e9ac7a42a6e3f1140666f7ed74) file imported in `edit.js` and `index.js` but spent hours struggling with it before I get it to work., and it shows all categories not just the parent.

So, over to the experts! I'm interested to see how you get this to work.

No rush!