How to List Jekyll Posts by Category
This post was
heavily inspired more or less copied from Joe Kampschmidt’s post How to list your jekyll posts by tags.
In his post, Joe shows how to create a list of posts sorted by the tags which they appear in. I wanted to achieve the same but instead listing by category rather than tag. I prefer categories as they are added into the URL when generating your site which I think is better for organisation (see here for the differences).