polyfill HTML5-History-API falls at initialization in IE6+

polyfill [HTML5-History-API](https://github.com/devote/HTML5-History-API) creates a new `history` object by means of VBScript, and if there was an appeal to the property `history` as global variable omitting the `window.` Library [HTML5-History-API](https://github.com/devote/HTML5-History-API) initialization fails.
Merge pull request #976 from devote/patch-1

polyfill HTML5-History-API falls at initialization in IE6+