Implemented ability to iterate over objects, ala for-in.

Also added the 'key' key to looped objects.
My goal is to make this {{@key}}, but am still working on it.
I would also like to unobtrusively make @key or @index work for arrays.

lib/handlebars/base.js

@@ -64,20 +64,33 @@ Handlebars.createFrame = Object.create || function(object) {
 
 Handlebars.registerHelper('each', function(context, options) {
   var fn = options.fn, inverse = options.inverse;
-  var ret = "", data;
+  var i = 0, ret = "", data;
 
   if (options.data) {
     data = Handlebars.createFrame(options.data);
   }
 
-  if(context && context.length > 0) {
-    for(var i=0, j=context.length; i<j; i++) {
-      if (data) { data.index = i; }
-      ret = ret + fn(context[i], { data: data });
+  if(context && typeof context === 'object') {
+    if(context instanceof Array){
+      for(var j = context.length; i<j; i++) {
+        if (data) { data.index = i; }
+        ret = ret + fn(context[i], { data: data });
+      }
+    } else {
+      for(var key in context) {
+        if(context.hasOwnProperty(key)) {
+          if(data) { data.key = key; }
+          ret = ret + fn(context[key], {data: data});
+          i++;
+        }
+      }
     }
-  } else {
+  }
+
+  if(i === 0){
     ret = inverse(this);
   }
+
   return ret;
 });