/**
* Adds an expert response to a question. This action has the effect of generating an email to the person asking
* the questions as well as setting the question state to read + responded for this expert
*
* @param $questionId
* @param $expertUserName
* @param $responseText
*
* @return \Responses
*/
public function addResponse($questionId, $expertUserName, $responseText)
{
$response = new \Responses();
$response->setQuestionId($questionId);
$response->setExpert($expertUserName);
$response->setResponse($responseText);
$response->save();
return $response;
}