title: Make text scrollable within div
body: <p>I am looking to make some lengthy text contained into a <code>div</code> where the text can be viewed by scrolling up or down. 
  Right now the "description" text is rendered like so <code>&lt;%= @pin.description.html_safe %&gt;</code> and is inside a <code>&lt;div class="panel-body&gt;</code> (I'm using <strong>Bootstrap</strong>). </p>