title: Browser language detection
body: <p>I need in my Angular2 app detect browser language. Based on this language I need to send request (to a REST API of backend) with localization and IDs of my variables, which I need to translate. After that I received response with translated variables.</p>
  
  <p>So the app workflow is to detect browser language, ok it is for example <code>en-US</code>, after that I am going to sent request to backend give me lang for en-US for variables with IDs 1,2,3,4,5. The response is <code>{{id:1, var:pay}, {id:1, var:title}}</code> etc.</p>
  
  <p>So how can I detect with Angular2 (developed with typescript) browser language?</p>