[bug] Starting a container with exit value 11 should not return 0.

[sunyuan3]

Ⅰ. Issue Description

Starting a container with exit value 11 should not return 0.

Ⅱ. Describe what happened

Starting a container with exit value 11 returns 0.
In docker, the operation returns 11.

Ⅲ. Describe what you expected to happen

Starting a container with exit value 11 returns 11.

Ⅳ. How to reproduce it (as minimally and precisely as possible)

#pouch create reg.docker.alibaba-inc.com/base/busybox:latest sh -c "exit 11"
container ID: d496b381e6937c26b7333029a02ad213f316b231749d03431d45e304b7e41ae8, name: d496b3

[[email protected] /root/pouchtest/testcases/api_cli]
#pouch start -a d496b3

[[email protected] /root/pouchtest/testcases/api_cli]
#echo $?
0

[[email protected] /root/pouchtest/testcases/api_cli]
#pouch ps
Name   ID   Status   Created   Image   Runtime

Ⅴ. Anything else we need to know?

NA

Ⅵ. Environment:

• pouch version (use pouch version):
  #pouch version
  Os: linux
  Version: 0.3.0
  APIVersion: 1.24
  Arch: amd64
  BuildTime: Fri, 30 Mar 2018 11:50:18 +0800
  GitCommit: 69e66f0
  GoVersion: go1.9.1
  KernelVersion: 3.10.0-327.ali2015.alios7.x86_64

• OS (e.g. from /etc/os-release):
  #cat /etc/os-release
  NAME="Alibaba Group Enterprise Linux Server"
  VERSION="7.2 (Paladin)"
  ID="alios"
  ID_LIKE="fedora"
  VERSION_ID="7.2"
  PRETTY_NAME="Alibaba Group Enterprise Linux Server 7.2 (Paladin)"
  ANSI_COLOR="0;31"
  CPE_NAME="cpe:/o:alibaba:enterprise_linux:7.2:GA:server"
  HOME_URL="https://www.aliyun.com/"
  BUG_REPORT_URL="http://bbs.aliyun.com/"

ALIBABA_BUGZILLA_PRODUCT="Alibaba Group Enterprise Linux 7"
ALIBABA_BUGZILLA_PRODUCT_VERSION=7.2
ALIBABA_SUPPORT_PRODUCT="Alibaba Group Enterprise Linux"
ALIBABA_SUPPORT_PRODUCT_VERSION=7.2

• Kernel (e.g. uname -a):
  #uname -a
  Linux e100069194102.zmf 3.10.0-327.ali2015.alios7.x86_64 add travis.yml for CI #1 SMP Sun Feb 11 16:23:43 CST 2018 x86_64 x86_64 x86_64 GNU/Linux

• Install tools:

• Others:

[Ace-Tang]

pouch exec also has such problem, I will fix in another pr.