RN Could not connet to development server

遇到的问题:
Failed to load bundle(http://...) with error:(Could not connet to development server);
node进程也会卡住:at process._tickCallback

解决方法:
1: sudo lsof -i :8081

查看占用8081端口的任务

2: sudo kill -9 PID

(第一行的PID)
干掉占用8081端口的第一个任务

此时终端会显示:
```
Process terminated. Press <enter> to close the window
```
然后 enter 会显示

```    
logout
Saving session...
...copying shared history...
...saving history...truncating history files...
...completed.

[进程已完成]
```

3: npm start

模拟器 Reload