title: Yii not showing any error
body: <p>Can't make Yii to show error to webbrowser. Configured custom error handler in <em>config</em>:</p>
  
  <pre><code>'errorHandler' =&gt; array(
              // use 'site/error' action to display errors
              'errorAction' =&gt; 'site/error',
          ),
  </code></pre>
  
  <p>But all errors only got written to <em>application.log</em> and then Apache servers empty page with <em>error 500</em>. How to make Yii print errors to the screen?</p>
  
  <p><em>index.php</em>:</p>
  
  <pre><code>// remove the following lines when in production mode
  defined('YII_DEBUG') or define('YII_DEBUG', true);
  // specify how many levels of call stack should be shown in each log message
  defined('YII_TRACE_LEVEL') or define('YII_TRACE_LEVEL',3);
  </code></pre>