Highlight comment based on anchor in URL

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

CHANGELOG

@@ -2,6 +2,7 @@ Please view this file on the master branch, on stable branches it's out of date.
 v 8.2.0 (unreleased)
   - Show last project commit to default branch on project home page
+  - Highlight comment based on anchor in URL
 v 8.1.0 (unreleased)
   - Fix error preventing displaying of commit data for a directory with a leading dot (Stan Hu)

app/assets/stylesheets/framework/timeline.scss

@@ -13,6 +13,10 @@
     border-bottom: 1px solid #ECEEF1;
     border-right: 1px solid #ECEEF1;
+    &:target {
+      background: $hover;
+    }
+
     &:last-child {
       border-bottom: none;
     }