policies.py: Remove max reconnect attempts

This was kept this way to preserve legacy behavior, but I think changing
the behavior will be less of a problem than what the current behavior
causes.
The policy is used for reconnections (for example, reconnecting control
connection). If reconnect policy finishes generation (it will do so
after 64 attempts before my change), then the reconnector finish and the
driver won't attempt reconnection anymore. This would be a terrible
situation.

Author: Lorak-mmk

cassandra/policies.py

@@ -773,7 +773,7 @@ class ConstantReconnectionPolicy(ReconnectionPolicy):
     in-between each reconnection attempt.
     """
 
-    def __init__(self, delay, max_attempts=64):
+    def __init__(self, delay, max_attempts=None):
         """
         `delay` should be a floating point number of seconds to wait in-between
         each attempt.
@@ -807,10 +807,7 @@ class ExponentialReconnectionPolicy(ReconnectionPolicy):
     trying to reconnect at exactly the same time.
     """
 
-    # TODO: max_attempts is 64 to preserve legacy default behavior
-    # consider changing to None in major release to prevent the policy
-    # giving up forever
-    def __init__(self, base_delay, max_delay, max_attempts=64):
+    def __init__(self, base_delay, max_delay, max_attempts=None):
         """
         `base_delay` and `max_delay` should be in floating point units of
         seconds.