`telnetConnect` blocks

If Keep Alive fails because the F/T sensor disconnected from Wifi, [`telnetConnect`](https://github.com/personalrobotics/forque_sensor_hardware/blob/f7579ddf52c90196bbd42a8c014105126ac5aee9/src/main.cpp#L159) blocks and doesn't return even after the F/T sensor reconnected. That also blocks proper processing of SIGINT. We should add a timeout to the telnet connection call.