docs(guide/$location): correct link to HTML5 draft section 5.5 (history api)

Previous link url is no longer served, responds with bad link (error 404). This change corrects the
URL to point to section 5.5 of the draft. The old URL appears to have been removed from service in
2012.

Corrects the link to "History API"

Closes #6225

Author: Stéphane Reynaud

docs/content/guide/dev_guide.services.$location.ngdoc

@@ -160,7 +160,7 @@ encoded.
 
 `$location` service has two configuration modes which control the format of the URL in the browser
 address bar: **Hashbang mode** (the default) and the **HTML5 mode** which is based on using the
-HTML5 {@link http://www.w3.org/TR/html5/history.html History API}. Applications use the same API in
+HTML5 {@link http://www.w3.org/TR/html5/browsers.html#history History API}. Applications use the same API in
 both modes and the `$location` service will work with appropriate URL segments and browser APIs to
 facilitate the browser URL change and history management.