title: Laravel 5 input old is empty
body: <p>My routes is here <br></p>
  
  <pre><code>Route::get('sign-up', ['as' =&gt; 'signUp', 'uses' =&gt; 'UserController@signUpGet']);
  Route::post('sign-up', ['as' =&gt; 'signUpPost', 'uses' =&gt; 'UserController@signUpPost']);
  </code></pre>
  
  <p>Controller
  <br></p>
  
  <pre><code>return redirect('signUp')-&gt;withInput();
  </code></pre>
  
  <p>And View <br></p>
  
  <pre><code>    &lt;form role="form" method="POST" action="{{route('signUpPost')}}"&gt; 
          &lt;input type="text" class="form-control" name="username" value="{{ old('username') }}"&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>The {{old()}} function return empty value.
  <br>
  EDIT
  <br>
  I took<br></p>
  
  <pre><code>NotFoundHttpException in RouteCollection.php line 145:
  </code></pre>