title: Passing multiple parameters in a hyperlink in yii2 with clean urls, Html::a() doesnt generate clean url
body: <p>I am trying to generate a hyper link by the method mentioned in 
  <a href="http://www.yiiframework.com/doc-2.0/guide-helper-html.html#hyperlinks">http://www.yiiframework.com/doc-2.0/guide-helper-html.html#hyperlinks</a> like this </p>
  
  <pre><code> Html::a('&lt;b&gt;Register&lt;/b&gt;', 
      ['story/create', array('id' =&gt;39,'usr'=&gt;'11')], 
      ['class' =&gt; 'profile-link'])
  </code></pre>
  
  <p>I want to get url like  <code>story/create/id/39/usr/11</code></p>
  
  <p>But it is generating as </p>
  
  <pre><code>story/create?1%5Bid%5D=39&amp;1%5Busr%5D=1
  </code></pre>
  
  <p>I have enabled the clean url functionality of yii2 like</p>
  
  <pre><code>  'urlManager' =&gt; [
          'class' =&gt; 'yii\web\UrlManager',
          // Disable index.php
          'showScriptName' =&gt; false,
          // Disable r= routes
          'enablePrettyUrl' =&gt; true,
          'rules' =&gt; array(
                  '&lt;controller:\w+&gt;/&lt;id:\d+&gt;' =&gt; '&lt;controller&gt;/view',
                  '&lt;controller:\w+&gt;/&lt;action:\w+&gt;/&lt;id:\d+&gt;' =&gt; '&lt;controller&gt;/&lt;action&gt;',
                  '&lt;controller:\w+&gt;/&lt;action:\w+&gt;' =&gt; '&lt;controller&gt;/&lt;action&gt;',
          ),
          ], also.
  </code></pre>
  
  <p>How this can be achieved?</p>