title: Sequelize.js delete query?
body: <p>Is there a way to write a delete/deleteAll query like findAll?</p>
  
  <p>For example I want to do something like this (assuming MyModel is a Sequelize model...):</p>
  
  <pre><code>MyModel.deleteAll({ where: ['some_field != ?', something] })
      .on('success', function() { /* ... */ });
  </code></pre>