Use augment.js for improved cross browser compatibility

Remove the quick hack for that I added for Array.forEach and pull
in augment.js instead to add missing JS methods to older browsers.

app/assets/javascripts/application.js

@@ -2,10 +2,10 @@
 //= require jquery_ujs
 //= require jquery.autogrowtextarea
 //= require jquery.timers
+//= require augment
 //= require openlayers
 //= require i18n/translations
 //= require globals
-//= require compat
 //= require browse
 //= require export
 //= require map

app/assets/javascripts/compat.js

@@ -1,10 +0,0 @@
-/*
- * Implement Array.forEach for browsers which don't have it
- */
-if ( !Array.prototype.forEach ) {
-  Array.prototype.forEach = function(fn, scope) {
-    for(var i = 0, len = this.length; i < len; ++i) {
-      fn.call(scope || this, this[i], i, this);
-    }
-  }
-}