title: Add property to POCO class at runtime
body: <p>I selected <a href="https://github.com/ServiceStack/ServiceStack.OrmLite" rel="noreferrer">ServiceStack OrmLite</a> for my project which is a pure Data-Oriented application. I am willing to allow the end user to create his own Object Types defined in an XML format that will be used to generate classes at runtime using <a href="http://msdn.microsoft.com/en-us/library/y2k85ax6.aspx" rel="noreferrer">CodeDOM</a>.</p>
  
  <p>I will be also defining some "system" objects required by the application (i.e. <code>User</code>) but I cannot foresee all the properties the end user will use and therefore I am looking for a way to allow extending the classes I create in design time. Sample bellow</p>
  
  <pre><code>public class User
  {
      public Guid Uid { get; set; }
      public String Username { get; set; }
      public String Password { get; set; }
  }
  </code></pre>
  
  <p>The end user wants to have an <code>Email</code> and an <code>Address</code>. He should be able to add the 2 properties to the upper class and the whole class will be (which still can be used by OrmLite, since it allows overwriting :</p>
  
  <pre><code>public class User
  {
      public Guid Uid { get; set; }
      public String Username { get; set; }
      public String Password { get; set; }
      public String Email{ get; set; }
      public String Address { get; set; }
  }
  </code></pre>
  
  <p>I know that there might be a risk of doing so to crash the system (if the class is already instantiated) so I am looking for the best way to avoid this issue and mimic the need I have.</p>