Get rid of close_server.

src/ZEO/StorageServer.py

@@ -1190,8 +1190,6 @@ class StorageServer:
         if self.__thread is not None:
             self.__thread.join(join_timeout)
 
-    close_server = close
-
     def close_conn(self, conn):
         """Internal: remove the given connection from self.connections.
 

src/ZEO/runzeo.py

@@ -160,7 +160,7 @@ class ZEOServer:
             self.create_server()
             self.loop_forever()
         finally:
-            self.server.close_server()
+            self.server.close()
             self.clear_socket()
             self.remove_pidfile()