Attempt 2 to make windows happy with int64 random seed type

Author: marcharper

axelrod/random_.py

@@ -26,7 +26,7 @@ def randint(self, *args, **kwargs):
         return self._random.randint(*args, **kwargs)
 
     def random_seed_int(self):
-        return self.randint(0, 2**32-1, dtype='u8')
+        return self.randint(0, 2**32-1, dtype='int64')
 
     def choice(self, *args, **kwargs):
         return self._random.choice(*args, **kwargs)