Merge branch 'master' into develop

sleekxmpp/features/feature_mechanisms/mechanisms.py

@@ -99,7 +99,7 @@ class FeatureMechanisms(BasePlugin):
                 result[value] = creds.get('email', jid)
             elif value == 'channel_binding':
                 if sys.version_info >= (3, 3):
-                    result[value] = self.xmpp.socket.channel_binding()
+                    result[value] = self.xmpp.socket.get_channel_binding()
                 else:
                     result[value] = None
             elif value == 'host':

sleekxmpp/util/misc_ops.py

@@ -19,6 +19,9 @@ def bytes(text):
     :param text: Unicode text to convert to bytes
     :rtype: bytes (Python3), str (Python2.6+)
     """
+    if text is None:
+        return b''
+
     if sys.version_info < (3, 0):
         import __builtin__
         return __builtin__.bytes(text)