title: Add line breaks in mail function php
body: <p>I'd like to send email using mail function.
  Want to add line breaks as follows.</p>
  
  <pre><code>$msg = 'aaaaa'.'\r\n'.'bbbbbb'.'\r\n';
  $headers .= "Content-Type: text/plain; charset=\"utf-8\"\r\n";
  $to = 'test@test.com';
  mail($to,'Subject',$msg,$headers);
  </code></pre>
  
  <p>But not working.</p>
  
  <p>How can I send email as follows.</p>
  
  <p>aaaaa</p>
  
  <p>bbbbbb</p>