added redis-server
added redis-server

gitlabhq/gitlab-ci-runner,myrubapa/gitlab-ci-runner-centos,andrewmunsell/gitlab-ci-runner,mfittko/gitlab-ci-runner,moos3/gitlab-ci-runner-centos,Wolfium/gitlab-ci-runner-centos,cui-liqiang/gitlab-ci-runner,cui-liqiang/gitlab-ci-runner,andrewmunsell/gitlab-ci-runner,gitlabhq/gitlab-ci-runner,moos3/gitlab-ci-runner-centos,mfittko/gitlab-ci-runner,Wolfium/gitlab-ci-runner-centos,myrubapa/gitlab-ci-runner-centos