Travertino is a library describing constants and a base box model that can be used to define layout algorithms.
So, why is it called "travertino"?
Travertine (Travertino in Italian) is a type of limestone that has been used as a building material for thousands of years. The name derives from the Latin tiburtinus, meaning "of Tibur" - Tibur being a town near Rome that was the historical source of Travertine.
Travertine is the building material that was used to build the Colosseum.