Implemented _.init as per #319

underscore.js

@@ -323,6 +323,14 @@
     return slice.call(array, (index == null) || guard ? 1 : index);
   };
 
+  // Returns everything but the last entry of the array. Especcialy useful on
+  // the arguments object. Passing **n** will return all the values in
+  // the array, excluding the last N. The **guard** check allows it to work with
+  // `_.map`.
+  _.init = function(array, n, guard) {
+    return slice.call(array, 0, array.length - ((n == null) || guard ? 1 : n));
+  };
+
   // Get the last element of an array. Passing **n** will return the last N
   // values in the array. The **guard** check allows it to work with `_.map`.
   _.last = function(array, n, guard) {