router.jsx: Remove unnecessary parameter state and onEnter

This remove the warning `state is defined but never used`.

Close: #137

Author: Aditya Agarwal

src/router.jsx

@@ -27,7 +27,7 @@ import {parseRoute, buildRoute} from './route-utils';
 const routes = [
   // Redirect from `/dashboard` to `/`
   { path: '/dashboard',
-    onEnter: (state, replace) => browserHistory.push('/')
+    onEnter: () => browserHistory.push('/')
   },
   { path: '/',
     component: App,