Add a simple test for diagnostics
Better printing
With a bunch of prints

which helped us find the problem, which was that the SlowStrategy
was returning inner.next instead of wrapping it in another SlowStrategy
Mostly pretty-printing
Some good shrinkers EXCEPT for the stupid

initialization of the SlowTestPlayers based on the number of birds. Lame.
If we're going to initialize them why stop at n? Let's always do 20.
Always init the max birds. No issues
Clever checking for actor termination