SortHelper refactoring:

* multiple columns sort feature (#2871)
* CSS classes instead of an image tag to reflect the state of the column
* examples fixed (#2945)

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@2571 e93f8b46-1217-0410-a6f0-8f06a7374b81

public/stylesheets/application.css

@@ -142,6 +142,10 @@ table p {margin:0;}
 .odd {background-color:#f6f7f8;}
 .even {background-color: #fff;}
 
+a.sort { padding-right: 16px; background-position: 100% 50%; background-repeat: no-repeat; }
+a.sort.asc  { background-image: url(../images/sort_asc.png); }
+a.sort.desc { background-image: url(../images/sort_desc.png); }
+
 .highlight { background-color: #FCFD8D;}
 .highlight.token-1 { background-color: #faa;}
 .highlight.token-2 { background-color: #afa;}