fix urls for when we aren't running on the root

htdocs/features.js

@@ -1,6 +1,6 @@
 $(function(){
     var converter = new showdown.Converter();
-    $.ajax('/api/features').done(function(data){
+    $.ajax('api/features').done(function(data){
         var $table = $('table.features');
         $.each(data, function(name, details) {
             var requirements = $.map(details.requirements, function(r, name){
@@ -21,4 +21,4 @@ $(function(){
             );
         })
     });
-});
+});