Currently in the documentation, security groups and instance backup have their own category but only contain an about page. Features with only a single page shouldn't be in their own category.
Moved them to the usage category. Once we write dedicated pages for configuration, troubleshooting, etc. we can move them back.
Cleaned up some dirty whitespace
Moved the instance backup and security groups page to usage. Also put…
… some whitespace in the file for better readability
Rebuilt the site after merging #575