title: Use of unresolved operator '<~'
body: <p>I am using ReactiveCocoa 5.0 alpha 3, ReactiveSwift and Swift 3</p>
  
  <p>I am having issues with binding my UITextField to a MutableProperty.</p>
  
  <p>In ReactiveCocoa 4, I used this:-</p>
  
  <pre><code>extension UITextField {
      func signalProducer() -&gt; SignalProducer&lt;String, NoError&gt; {
          return self.rac_textSignal().toSignalProducer()
              .map { $0 as! String }
              .flatMapError { _ in return SignalProducer&lt;String, NoError&gt;.empty }
      }
  }
  
  viewModel.email &lt;~ emailTextField.signalProducer()
  </code></pre>
  
  <p>But now in ReactiveCocoa 5, I am not able to do that. From what I understand, I am supposed to do something like this I guess:-</p>
  
  <pre><code>viewModel.email &lt;~ emailTextField.reactive.textValues
  </code></pre>
  
  <p>But either it says '&lt;~' is unresolved or textValues is not a property.</p>
  
  <p>Please help me bind this.</p>