feature: add node ip and sn into daemon labels

[allencloud]

Signed-off-by: Allen Sun allensun.shl@alibaba-inc.com

Ⅰ. Describe what this PR did

This PR adds two default labels in pouchd daemon:

• node_ip: this is node ip which is fetched by hostname -i;
• serial number: machine's serial number

Ⅱ. Does this pull request fix one issue?

none

Ⅲ. Describe how you did it

Ⅳ. Describe how to verify it

root@ubuntu:~/go/src/github.com/alibaba/pouch# pouch info
Containers: 8
 Running: 8
 Paused: 0
 Stopped: 0
Images:  0
ID:
Name: ubuntu
Server Version: 0.4.0-dev
Storage Driver: overlayfs
Driver Status: []
Logging Driver:
Cgroup Driver:
runc: <nil>
containerd: <nil>
Security Options: []
Kernel Version: 4.4.0-87-generic
Operating System: "Ubuntu 16.04.3 LTS"
OSType: linux
Architecture:
HTTP Proxy:
HTTPS Proxy:
Registry: https://index.docker.io/v1/
Experimental: false
Debug: false
Labels:
  node_ip=127.0.1.1
  SN=0
CPUs: 1
Total Memory: 1.953 GiB
Pouch Root Dir: /var/lib/pouch
LiveRestoreEnabled: false
Daemon Listen Addresses: [unix:///var/run/pouchd.sock]

Ⅴ. Special notes for reviews

none

[codecov-io]

Codecov Report

Merging #1134 into master will increase coverage by 0.07%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1134      +/-   ##
==========================================
+ Coverage   15.62%   15.69%   +0.07%     
==========================================
  Files         172      171       -1     
  Lines        9691     9682       -9     
==========================================
+ Hits         1514     1520       +6     
+ Misses       8068     8052      -16     
- Partials      109      110       +1

Impacted Files	Coverage Δ
client/client.go	33.33% <0%> (-3.04%)	⬇️
daemon/mgr/container_types.go	15.38% <0%> (ø)	⬆️
ctrd/snapshot.go	0% <0%> (ø)	⬆️
apis/server/container_bridge.go	0% <0%> (ø)	⬆️
cli/command.go
daemon/mgr/container.go	4.98% <0%> (+0.11%)	⬆️

[yyb196]

LGTM

[Letty5411]

LGTM