Document the new modification argument for payment.manager.PaymentManager.authorize

payment/manager.py

@@ -566,6 +566,7 @@ class PaymentManager( object ):
         anonymous: whether this pledge is anonymous
         premium: the premium selected by the supporter for this transaction
         paymentReason:  a memo line that will show up in the Payer's Amazon (and Paypal?) account
+        modification: whether this authorize call is part of a modification of an existing pledge 
         
         return value: a tuple of the new transaction object and a re-direct url.  If the process fails,
                       the redirect url will be None
@@ -626,7 +627,7 @@ class PaymentManager( object ):
             # that the transaction has successfully completed; triggering notifications
             # when the transaction is initiated risks sending notifications on transactions
             # that for whatever reason fail.  will need other housekeeping to handle those.
-            if modification==True:
+            if modification:
                 pledge_modified.send(sender=self, transaction=t, status="increased")
             else:
                 pledge_created.send(sender=self, transaction=t)