Show colored icons like in the admin listing

app/views/groups/projects.html.haml

@@ -12,6 +12,7 @@
     - @projects.each do |project|
       %li
         .list-item-name
+          %span{ class: visibility_level_color(project.visibility_level) }
             = visibility_level_icon(project.visibility_level)
           %strong= link_to project.name_with_namespace, project
         .pull-right