title: Add a column to an existing entity in Symfony
body: <p>I've been playing around with Symfony on my web server and I've been creating entity with doctrine for my database. I wanted to add a column to one of these entity... I wanted to do something like:</p>
  
  <pre><code>php app/console doctrine:modify:entity
  </code></pre>
  
  <p>Now I know that this command doesn't exists, but is there a way (without doing a whole migration) to simply add a column.</p>
  
  <p>P.S. I know I could open the php file and textually add the column there and then update the schema, but I'm distributing this to some clients and I like a more "command-line-like" approach.</p>