Fix: Specify model and 'url' key in form options

Otherwise, searching in Contact page gets blackholed.

Closes #510

Nodes/View/Elements/search.ctp

@@ -1,5 +1,5 @@
 <?php
-	echo $this->Form->create(null, array('admin' => false, 'plugin' => 'nodes', 'controller' => 'nodes', 'action' => 'search'));
+	echo $this->Form->create('Node', array('url' => array('admin' => false, 'plugin' => 'nodes', 'controller' => 'nodes', 'action' => 'search')));
 	$this->Form->unlockField('q');
 	echo $this->Form->input('q', array(
 		'label' => false,