title: Sails.js query model filtering by collection attribute
body: <p>Suppose that I have the following models in Sails.js v0.10:</p>
  
  <pre><code>Person.js
  
  module.exports = {
  
    attributes: {
  
      name: 'string',
  
      books: {
        collection: 'book',
        via: 'person'
      }
  
    } 
  };
  
  Book.js
  
  module.exports = {
  
    attributes: {
  
      name: 'string',
  
      person: {
        model: 'person'
      }
  
    } 
  };
  </code></pre>
  
  <p>I want a query to return an array of people that have a certain associated book. I would like to do something like the following query, but i don't know how:</p>
  
  <pre><code>  Person.find()
      .populate('books')
      .where({ books.name: 'Game of Thrones'})
      .exec(function(err, person) {
        if (err) return res.send(err, 500);
        res.json(person);
      });
  </code></pre>
  
  <p>Any ideas if this is possible to do using a simple query?</p>