Add node_map check feature

To keep insertion order.

For example, these response may be easy to parse when keep order.
And easy to understand for human when debugging and logging.

```
STAT 192.168.0.1:12201:role slave
STAT 192.168.0.1:12201:state active
STAT 192.168.0.1:12201:partition 2
STAT 192.168.0.1:12201:balance 0
STAT 192.168.0.1:12201:thread_type 57
STAT 192.168.0.1:12201:role slave
STAT 192.168.0.1:12201:state active
STAT 192.168.0.1:12201:partition 3
STAT 192.168.0.1:12201:balance 0
STAT 192.168.0.1:12201:thread_type 58
STAT 192.168.0.2:12201:role slave
STAT 192.168.0.2:12201:state active
STAT 192.168.0.2:12201:partition 0
STAT 192.168.0.2:12201:balance 0
STAT 192.168.0.2:12201thread_type 43
STAT 192.168.0.2:12201:role slave
STAT 192.168.0.2:12201:state active
STAT 192.168.0.2:12201:partition 1
STAT 192.168.0.2:12201:balance 0
STAT 192.168.0.2:12201:thread_type 44
```