Merge branch 'event-last-push-styling-fix' into 'master'

event-last-push styling fix

When viewing a fresh install of GitLab on a mobile device after a branch with a name of sufficient length, the broken styling can be seen as follows:

![Screen Shot 2015-01-05 at 9.37.32 PM](https://gitlab.com/uploads/cloudwindhk/gitlab-ce/9b3ca84f1a/Screen_Shot_2015-01-05_at_9.37.32_PM.png)

I modified the css for .event-last-push and .event-last-push-text to make it look correct:

![Screen Shot 2015-01-05 at 9.37.50 PM](https://gitlab.com/uploads/cloudwindhk/gitlab-ce/43d5a912b3/Screen_Shot_2015-01-05_at_9.37.50_PM.png)

As this is a purely css change, I don't believe it will break any tests. The only occurrence of .event-last-push* is in ./app/views/events/_event_last_push.html.haml

See merge request !279

app/assets/stylesheets/sections/events.scss

@@ -145,8 +145,12 @@
  * Last push widget
  */
 .event-last-push {
+  overflow: auto;
   .event-last-push-text {
-    @include str-truncated(75%);
+    @include str-truncated(100%);
+    float:left;
+    margin-right: -150px;
+    padding-right: 150px;
     line-height: 24px;
   }
 }