Include a count of the number of tickets shown vs recorded for each milestone
    
    On the roadmap page there is now a count diplayed of the number of tickets
    shown vs the number of ticket recorded for this milestone.
    
    Fixes https://pagure.io/pagure/issue/2689
    
    Signed-off-by: Pierre-Yves Chibon <pingou@pingoured.fr></pingou@pingoured.fr>