title: ReactiveList - Check if property of any list item changes
body: <p>I have a <code>ReactiveList&lt;SomeObject&gt;</code>.</p>
  
  <p>What is the best way to detect if any item in the list has <code>SomeObject.SomeProperty</code> change?</p>
  
  <p>I could subscribe to each <code>SomeObject.SomeProperty</code> separately, but I feel like there must be a Better way?</p>