Merge ticket #11 Version Model の作成

commit 4d19a4f541522114e2aaa12e9b8dd884b15d2e35
Author: masato.tanoi <masato.tanoi@gmail.com>
Date:   Wed Mar 19 22:07:56 2014 +0900

    Version model の validate の設定

commit ff264da18709f2e8004f8747f4ed045999802484
Author: masato <masato@Macbook-Air.local>
Date:   Wed Mar 19 21:39:23 2014 +0900

    version model の作成