title: Shikashi: cannot access constant Hash exception
body: <p>Why do I get the Security Error <strong>"cannot access constant Hash"</strong> in this scenario using the Shikashi Gem?</p>
  
  <pre><code>include Shikashi
  
  privileges = Privileges.new
  privileges.instances_of(Hash).allow_all
  Sandbox.new.run(privileges, "arguments=Hash.new;")
  </code></pre>
  
  <p>Any insights? I need to run some ruby code in a Sandbox to see if its behaves nicely.</p>