"CADET-Core" being in the upper left corner of https://cadet.github.io/

The CADET website (https://cadet.github.io/)  pulls the title from the repo name and puts it in the upper left corner. We might want to consider setting this to static in the future, so it is just "CADET" again. However, this will only become relevant once the landing page is changed to introduce the CADET framework instead of CADET-Core.