Kill the cat

Simple reason: The cat wastes time. Whenever I have to run the DataModel tests locally it takes 11.5 seconds. Which is crazy when you compare it to the 1.4 seconds it takes without the cat. Yes, 88% of the time only for the cat animation. Come on. I think we all learned to appreciate a good joke but this is just not worth it.

Also see https://github.com/wmde/Diff/pull/17.