title: Ngrx-data select a single entity
body: <p>I am using ngrx-data plugin (runs on top of ngrx), and I'm trying to select a single entity from the store (that ngrx data calls 'Cache'). I found that you can add a single entity to the cache but I can't find the way to retrieve a single item (based on Id) from the store.</p>
  
  <p><strong>Do I have to write my own selector for this?</strong> I would assume a simple operation like this would be provided by ngrx-data</p>