Create Relation Between Comment and Attachment

[HowdyMcGee]

On the WordPress Stack Exchange there was a question to delete images attached to a comment whenever the comment was deleted, a cleanup process. This lead to digging into some of the plugin code and the database and found there is currently no real relation between the comment and the attachment. The only relation was that the attachment was actually inserted as html into the comment.

My proposition is to assign some kind of ID relation, comment ID to Attachment ID so it's easier in the long run to related the two.