chore(remote): better super-class call syntax

Python :) !!

Related to gitpython-developers#451

Author: Byron

git/util.py

@@ -320,7 +320,7 @@ class CallableRemoteProgress(RemoteProgress):
 
     def __init__(self, fn):
         self._callable = fn
-        RemoteProgress.__init__(self)
+        super(CallableRemoteProgress, self).__init__()
 
     def update(self, *args, **kwargs):
         self._callable(*args, **kwargs)