Merge branch 'show_number_of_mrs_in_milestone_page' into 'master'

Show number of processed MRs in milestone page

closes #14025 

![Screen_Shot_2016-05-02_at_6.20.34_PM](/uploads/9208e58c0e0c77133bd73332ee3b3342/Screen_Shot_2016-05-02_at_6.20.34_PM.png)

See merge request !4006

app/views/shared/milestones/_merge_requests_tab.haml

@@ -3,10 +3,10 @@
 
 .row.prepend-top-default
   .col-md-3
-    = render 'shared/milestones/issuables', args.merge(title: 'Work in progress (open and unassigned)', issuables: merge_requests.opened.unassigned, id: 'unassigned')
+    = render 'shared/milestones/issuables', args.merge(title: 'Work in progress (open and unassigned)', issuables: merge_requests.opened.unassigned, id: 'unassigned', show_counter: true)
   .col-md-3
-    = render 'shared/milestones/issuables', args.merge(title: 'Waiting for merge (open and assigned)', issuables: merge_requests.opened.assigned, id: 'ongoing')
+    = render 'shared/milestones/issuables', args.merge(title: 'Waiting for merge (open and assigned)', issuables: merge_requests.opened.assigned, id: 'ongoing', show_counter: true)
   .col-md-3
-    = render 'shared/milestones/issuables', args.merge(title: 'Rejected (closed)', issuables: merge_requests.closed, id: 'closed')
+    = render 'shared/milestones/issuables', args.merge(title: 'Rejected (closed)', issuables: merge_requests.closed, id: 'closed', show_counter: true)
   .col-md-3
-    = render 'shared/milestones/issuables', args.merge(title: 'Merged', issuables: merge_requests.merged, id: 'merged', primary: true)
+    = render 'shared/milestones/issuables', args.merge(title: 'Merged', issuables: merge_requests.merged, id: 'merged', primary: true, show_counter: true)