title: SearchBar Ionic 3 doesn't work
body: <p>I get my data with angulasfire2 classes:</p>
  
  <pre><code>participantsList: AngularFireList&lt;any&gt;;
  participants: Observable&lt;any[]&gt;;
  filteredParts: Observable&lt;any[]&gt;;
  </code></pre>
  
  <p>In the constructor</p>
  
  <pre><code>this.participantsList = afDatabase.list('/paticipants');
  this.participants = this.participantsList.valueChanges();
  </code></pre>
  
  <p>I want to filter the data with a searchbar on the header of my page</p>
  
  <pre><code>if(this.searchword == "")
    this.filteredParts =  this.participants;
  
  else {
    this.filteredParts = this.participants.filter(guest =&gt; {return guest.name.toLowerCase().indexOf(this.searchword) &gt; -1});
  }
  </code></pre>
  
  <p>But it gives me an error:</p>
  
  <blockquote>
    <p>The property 'name' doesn't exist in type 'any[]'.</p>
  </blockquote>
  
  <p>I add a new participant with</p>
  
  <pre><code>handler: data =&gt; {
          const newParticipant = this.participantsList.push({});
  
          newParticipant.set({
            id: newParticipant.key,
            name: data.name,
            surname: data.surname,
            paid: false
          });
  </code></pre>
  
  <p>In my JSON file exported from firebase I have</p>
  
  <pre><code>{
  "paticipants" : {
  "-L66ZM7Vr4pOVjHrN-L7" : {
    "id" : "-L66ZM7Vr4pOVjHrN-L7",
    "name" : "Giacomo",
    "paid" : true,
    "surname" : "Tabarelli"
  },
  "-L66dd9_JBypdrDgE7Y4" : {
    "id" : "-L66dd9_JBypdrDgE7Y4",
    "name" : "Paola",
    "paid" : true,
    "surname" : "Sandonà"
  },
  "-L66dg5ONTW84onoQKp8" : {
    "id" : "-L66dg5ONTW84onoQKp8",
    "name" : "Gianni",
    "paid" : true,
    "surname" : "Turatta"
  }
  }
  </code></pre>
  
  <p>Can't understand how these classes work, is this the correct way to interact with firebase? Or maybe I can use other easy classes?</p>