Bump to v4.1.0.

_Stack.js

@@ -0,0 +1,28 @@
+define(['./_stackClear', './_stackDelete', './_stackGet', './_stackHas', './_stackSet'], function(stackClear, stackDelete, stackGet, stackHas, stackSet) {
+
+  /**
+   * Creates a stack cache object to store key-value pairs.
+   *
+   * @private
+   * @param {Array} [values] The values to cache.
+   */
+  function Stack(values) {
+    var index = -1,
+        length = values ? values.length : 0;
+
+    this.clear();
+    while (++index < length) {
+      var entry = values[index];
+      this.set(entry[0], entry[1]);
+    }
+  }
+
+  // Add functions to the `Stack` cache.
+  Stack.prototype.clear = stackClear;
+  Stack.prototype['delete'] = stackDelete;
+  Stack.prototype.get = stackGet;
+  Stack.prototype.has = stackHas;
+  Stack.prototype.set = stackSet;
+
+  return Stack;
+});