title: Angular, typescript change detection input text
body: <p>I can't find simple and easy solution how to detect change in my textfield.
  I dont want to use <code>(keypress)</code> because the user will sometimes paste values into the field. (onchange) for example is working only when user will blur field. And I want to detect change immediately.</p>
  
  <p>What is the easiest angular js $watch equivalent?</p>