Make uniform attribution "slide"

[Peter9192]

Currently there is not much room in the usecase page for attribution/more info. In practice, one way to do it is to add a last tab/page to the usecase. However, this does not really align with our layout that has a figure as main content.

A solution would be use a standard 'title slide' that shows the title, contributors (both people and institutes), logo's, etc. Ideally, this title slide would have a standardized EUCP themed layout. Additional text/info can still be added on the side panel.