title: Error on delete function cakephp3
body: <p>I have an issue with the cascade deletion, I'm using the default delete function and added the parameter true to allow cascade deletion so if I run: </p>
  
  <pre><code>$this-&gt;Users-&gt;delete($user,true); 
  </code></pre>
  
  <p>I get a fatal error:</p>
  
  <blockquote>
    <p>Unsupported operand types in
    /vendor/cakephp/cakephp/src/ORM/Table.php
    on line 1628</p>
  </blockquote>
  
  <p>And if I run it without the true parameter for cascade deletion:</p>
  
  <pre><code>$this-&gt;Users-&gt;delete($user); 
  </code></pre>
  
  <p>I get the an error because of the foreign keys:</p>
  
  <blockquote>
    <p>SQLSTATE[23000]: Integrity constraint violation: 1451 Cannot delete or
    update a parent row: a foreign key constraint fails
    (<code>real_estate</code>.<code>customers</code>, CONSTRAINT <code>fk_customer_users10</code> FOREIGN
    KEY (<code>user_id</code>) REFERENCES <code>users</code> (<code>id</code>) ON DELETE NO ACTION ON
    UPDATE NO ACTION)</p>
  </blockquote>