Remove 'Self-Maintaining by Design' from splash and home pages; add developer tools overview

## Summary Remove the 'Self-Maintaining by Design' content from the splash page and home page. On the splash pages, display an overview of convenient developer tools with commercial descriptions, possibly including impression images, specs, and use cases. ## Steps to Reproduce 1. Navigate to the splash page or home page. 2. Observe the current 'Self-Maintaining by Design' content. ## Expected Behaviour The 'Self-Maintaining by Design' content is removed. The splash pages show an overview of convenient developer tools with commercial descriptions, and optionally impression images, specs, and use cases. ## Actual Behaviour The 'Self-Maintaining by Design' content is still present on the splash page and home page. ## Environment Not provided. --- *Reported by **retoor** via DevPlace.*