title: Modify middleware response
body: <p>My requirement: write a middleware that filters all "bad words" out of a response that comes from another subsequent middleware (e.g. Mvc). </p>
  
  <p>The problem: streaming of the response. So when we come back to our <code>FilterBadWordsMiddleware</code> from a subsequent middleware, which already wrote to the response, we are too late to the party... because response started already sending, which yields to the wellknown error <code>response has already started</code>...</p>
  
  <p>So since this is a requirement in many various situations -- how to deal with it?</p>