The dashboard was an early prototype idea for Ghost which was retired in 2015 after determining that it was not viable.
As we started looking into the viability and complexity of building a comprehensive analytics dashboard which would pull all your relevant site metrics into one place we came across more questions than answers.
All the paths we explored ended in creating a bad product. So in the end we had to decide between shipping something below our standards (and then suffering through maintaining it for the rest of time) – or letting the idea go. We opted for the latter. The dashboard was a lovely, but ultimately impractical idea!
Fortunately, though, you can still make the dashboard yourself really easily using Geckoboard, which is a fully thought-out, feature-complete product (with a team over 3x the size of Ghost's).
Here's more information about using Geckoboard and Ghost together.