Make the ConnectThread a daemon thread. This prevents an unsuccessful

ConnectThread from hanging the application on exit.

src/ZEO/zrpc/client.py

@@ -172,6 +172,7 @@ class ConnectionManager:
                 self.thread = t = ConnectThread(self, self.client,
                                                 self.addrlist,
                                                 self.tmin, self.tmax)
+                t.setDaemon(1)
                 t.start()
             if sync:
                 while self.connection is None: