Apply PEP8 fixes to the source tree.

matrix/server.py

@@ -61,8 +61,10 @@ class MatrixServer:
 
         # Queue of messages we need to send off.
         self.send_queue = deque()     # type: Deque[MatrixMessage]
+
         # Queue of messages we send off and are waiting a response for
         self.receive_queue = deque()  # type: Deque[MatrixMessage]
+
         self.message_queue = deque()  # type: Deque[MatrixMessage]
         self.ignore_event_list = []   # type: List[str]