fix example js

Previous example returned `Hello ,webpack ` rather than `Hello webpack`.

Author: Morgan Croney

content/get-started/index.md

@@ -33,9 +33,7 @@ function component () {
   var element = document.createElement('div');
 
   /* lodash is required for the next line to work */
-  element.innerHTML = _.map(['Hello','webpack'], function(item){
-    return item + ' ';
-  });
+  element.innerHTML = _.join(['Hello','webpack'], ' ');
 
   return element;
 }