Merge branch 'milestone_percentage' into 'master'

Show milestone percentage in detail page, fixes #485

#### What does this MR do?

This MR adds the percentage count also to the milestone detail page.

##### Why was this MR needed?

Currently, this is only shown in the overview list.

##### What are the relevant issue numbers?

#485

###### Screenshots

![Screenshot 2014-08-17 21.14.27](https://gitlab.com/uploads/razer6/gitlab-ce/27e6f20bf2/Screenshot_2014-08-17_21.14.27.png)

See merge request !170

app/views/projects/milestones/show.html.haml

@@ -47,6 +47,8 @@
       #{@milestone.closed_items_count} closed
       –
       #{@milestone.open_items_count} open
+       
+      %span.light #{@milestone.percent_complete}% complete
       %span.pull-right= @milestone.expires_at
     .progress.progress-info
       .progress-bar{style: "width: #{@milestone.percent_complete}%;"}