Access utils methods via modules

Allows for monkey patching (under ES5 systems). This somewhat mirrors
the proposed behavior in https://github.com/square/es6-module-transpiler/issues/37
but applies the behavior via manual code changes rather than compiler
support.

lib/handlebars/base.js

@@ -1,6 +1,5 @@
-/*jshint eqnull: true */
-
-import { extend, isEmpty } from "./utils";
+/*globals Exception, Utils */
+module Utils from "./Utils";
 import Exception from "./exception";
 
 export var VERSION = "1.0.0";
@@ -48,7 +47,7 @@ HandlebarsEnvironment.prototype = {
   registerHelper: function(name, fn, inverse) {
     if (toString.call(name) === objectType) {
       if (inverse || fn) { throw new Exception('Arg not supported with multiple helpers'); }
-      extend(this.helpers, name);
+      Utils.extend(this.helpers, name);
     } else {
       if (inverse) { fn.not = inverse; }
       this.helpers[name] = fn;
@@ -57,7 +56,7 @@ HandlebarsEnvironment.prototype = {
 
   registerPartial: function(name, str) {
     if (toString.call(name) === objectType) {
-      extend(this.partials,  name);
+      Utils.extend(this.partials,  name);
     } else {
       this.partials[name] = str;
     }
@@ -148,7 +147,7 @@ function registerDefaultHelpers(instance) {
   instance.registerHelper('with', function(context, options) {
     if (isFunction(context)) { context = context.call(this); }
 
-    if (!isEmpty(context)) return options.fn(context);
+    if (!Utils.isEmpty(context)) return options.fn(context);
   });
 
   instance.registerHelper('log', function(context, options) {
@@ -182,6 +181,6 @@ export function log(level, obj) { logger.log(level, obj); }
 
 export var createFrame = function(object) {
   var obj = {};
-  extend(obj, object);
+  Utils.extend(obj, object);
   return obj;
 };

lib/handlebars/runtime.js

@@ -1,5 +1,6 @@
+/*global Utils */
+module Utils from "./utils";
 import Exception from "./exception";
-import { escapeExpression, extend } from "./utils";
 import { COMPILER_REVISION, REVISION_CHANGES } from "./base";
 
 function checkRevision(compilerInfo) {
@@ -49,7 +50,7 @@ export function template(templateSpec, env) {
 
   // Just add water
   var container = {
-    escapeExpression: escapeExpression,
+    escapeExpression: Utils.escapeExpression,
     invokePartial: invokePartialWrapper,
     programs: [],
     program: function(i, fn, data) {
@@ -66,8 +67,8 @@ export function template(templateSpec, env) {
 
       if (param && common && (param !== common)) {
         ret = {};
-        extend(ret, common);
-        extend(ret, param);
+        Utils.extend(ret, common);
+        Utils.extend(ret, param);
       }
       return ret;
     },