dockerfile: upgrade to `sameersbn/ubuntu:14.04.20150805
dockerfile: upgrade to `sameersbn/ubuntu:14.04.20150805

sameersbn/docker-gitlab-ci,sameersbn/docker-gitlab-ci,adiferd/docker-gitlab-ci,youhong316/docker-gitlab-ci,youhong316/docker-gitlab-ci,adiferd/docker-gitlab-ci