ISO release version and build id should be in the ISO

[LalatenduMohanty]

Release version and build ID should be part of the ISO i.e. Similar to https://github.com/minishift/minishift-centos-iso/blob/master/Makefile#L36-L37

[LalatenduMohanty]

Seems like /etc/os-release file has outdated information. We need fix this as part of this issue.

$ minishift ssh
                        ##         .
                  ## ## ##        ==
               ## ## ## ## ##    ===
           /"""""""""""""""""\___/ ===
      ~~~ {~~ ~~~~ ~~~ ~~~~ ~~~ ~ /  ===- ~~~
           \______ o           __/
             \    \         __/
              \____\_______/
 _                 _   ____     _            _
| |__   ___   ___ | |_|___ \ __| | ___   ___| | _____ _ __
| '_ \ / _ \ / _ \| __| __) / _` |/ _ \ / __| |/ / _ \ '__|
| |_) | (_) | (_) | |_ / __/ (_| | (_) | (__|   <  __/ |
|_.__/ \___/ \___/ \__|_____\__,_|\___/ \___|_|\_\___|_|
Boot2Docker version 1.11.2, build HEAD : 7fc7575 - Thu Oct 27 17:23:17 UTC 2016
Docker version 1.11.2, build b9f10c9

docker@minishift:~$ cat /etc/os-release 
NAME=Boot2Docker
VERSION=1.11.2
ID=boot2docker
ID_LIKE=tcl
VERSION_ID=1.11.2
PRETTY_NAME="Boot2Docker 1.11.2 (TCL 7.2); HEAD : 7fc7575 - Thu Oct 27 17:23:17 UTC 2016"
ANSI_COLOR="1;34"
HOME_URL="http://boot2docker.io"
SUPPORT_URL="https://github.com/boot2docker/boot2docker"
BUG_REPORT_URL="https://github.com/boot2docker/boot2docker/issues"

[LalatenduMohanty]

FIxed by 587b4bf