LinkedInAtticGH-32 - populate dust.helpers using iteration

in lib/dust-helpers.js

force a failing script loading order by reworking existing specRunners
- server - sandwich dust.helpers.tapper assignment between dust and
  dust.helpers assignment
- client - use LABjs to force a specific script-loading order to achieve
  equivalent effect as the server

lib/dust-helpers.js

@@ -501,6 +501,8 @@ var helpers = {
 
 };
 
-dust.helpers = helpers;
+for (var key in helpers) {
+  dust.helpers[key] = helpers[key];
+}
 
 })(typeof exports !== 'undefined' ? module.exports = require('dustjs-linkedin') : dust);