title: CKEditor: Allow video embed code
body: <p>I am using CKEditor and want to allow the insertion of embed code from YouTube, Vimeo etc.
  CKEditor turns all tags into HTML Chars equivalent, which is good, but I want it to make exceptions for this kind of content. iFrames seem to be how it's done nowadays, so how can I tell CKEditor to leave iFrame tags alone?</p>
  
  <p>Thank you.</p>