Merge pull request #1339 from gmaclennan/patch-1

fix docs history={HashHistory}

Author: ryanflorence

doc/00 Guides/0 Overview.md

@@ -141,7 +141,7 @@ var App = React.createClass({
 // Finally we render a `Router` component with some `Route`s, it'll do all
 // the fancy routing stuff for us.
 React.render((
-  <Router history={HashHistory}>
+  <Router history={new HashHistory()}>
     <Route path="/" component={App}>
       <Route path="about" component={About}/>
       <Route path="inbox" component={Inbox}/>
@@ -162,7 +162,7 @@ var routes = {
   ]
 };
 
-React.render(<Router history={HashHistory} children={routes}/>, document.body):
+React.render(<Router history={new HashHistory()} children={routes}/>, document.body):
 ```
 
 Adding more UI
@@ -191,7 +191,7 @@ var Inbox = React.createClass({
 });
 
 React.render((
-  <Router history={HashHistory}>
+  <Router history={new HashHistory()}>
     <Route component={App}>
       <Route path="about" component={About}/>
       <Route path="inbox" component={Inbox}>