title: Google recaptcha validation in yii2 always fails
body: <p>I use <code>himiklab/yii2-recaptcha-widget</code>. I always get a validation error when I submit the form.</p>
  
  <pre><code>{"captcha":["The verification code is incorrect."]}.
  </code></pre>
  
  <p>Form:</p>
  
  <pre><code>$form-&gt;field($model, 'captcha',['template' =&gt; "{input}\n{hint}\n{error}"])-&gt;widget(
              \himiklab\yii2\recaptcha\ReCaptcha::className(),
              [
              'siteKey' =&gt; &lt;mysitekey&gt;,
              'widgetOptions' =&gt; ['id'=&gt;'recaptcha1']
              ]) 
  </code></pre>
  
  <p>Controller:</p>
  
  <pre><code>if(isset($_POST['Contact'])){
              if ($model-&gt;load(Yii::$app-&gt;request-&gt;post()) &amp;&amp; $model-&gt;save()) {
  </code></pre>
  
  <p>What am I doing wrong?</p>