allow separator in div class="verse"

[lindheli]

Adding <hr class="separator"> in a poem results in a validation error. Would it be possible to allow that?
An example which results in a validation error:

<div class="verse">
   <p class="linegroup">
      <span class="line">I en skål på bordet</span>
      <br/>
      <span class="line">det röda äpplet</span>
   </p>
   <hr class="separator"/>
   <p class="linegroup">
      <span class="line">Vill du smaka på äpplet</span>
      <br/>
      <span class="line">jag orkar inte</span>
      <br/>
      <span class="line">inte nu</span>
   </p>