Issue #1555: Use function after definition

Fixes some `JSLint` inspection violations.

Description:
>JSLint: 'main' was used before it was defined.

src/site/resources/js/anchors.js

@@ -1,7 +1,5 @@
 'use strict';
 
-window.addEventListener('load', main);
-
 function main() {
     var url = window.location.href;
     var anchors = document.getElementsByTagName('h2');
@@ -20,4 +18,6 @@ function main() {
         anchors[i].appendChild(anchor);
     }
 
-}
+}
+
+window.addEventListener('load', main);