changed travis configuration: added gemfile
changed travis configuration: added gemfile

Undev/redmine_undev_git,Restream/redmine_undev_git,Undev/redmine_undev_git,pawwal/redmine_undev_git,Undev/redmine_undev_git,pawwal/redmine_undev_git,Restream/redmine_undev_git,pawwal/redmine_undev_git,Restream/redmine_undev_git