title: Filter Complex Objects in PrimeNG Turbo Table
body: <p>Lets say I have a table and I'm pulling in a list of clients. Maybe one of the parameters is an address object which contains parameters like city, state, zip etc. I can easily make any of those values appear in the table (E.g client.address.city) but because they are part of the address object I am unable to filter or sort by those values.</p>
  
  <p>This is currently what Material 2 offers for flattening out the data, giving users the ability to filter/sort.</p>
  
  <pre><code>this.dataSource.filterPredicate = (client: Client, filter) =&gt; {
          let dataStr = client.step + client.name + client.interest.industry + client.interest.package + client.address.city + client.address.state + client.origin;
          return dataStr.toLowerCase().indexOf(filter) != -1; 
        }
  </code></pre>
  
  <p>How can I achieve something like this with primeng's turbo table?</p>