create draft has no method for retaining the attachment

[Nathan Humphreys]

I suspect this functionality has never existed, due to the draft and send pages sharing the same template this bug is present.

When creating a draft email within an issue, after adding an attachment it is not retained for future draft updates or present when the email is actually sent to the mail queue.

Steps to re-produce:

1) Load up an issue
2) Click 'Create Draft'
3) Fill out required form fields including adding an attachment
4) Save Draft
5) View Draft and observe the attachment dialog is present and there is also no indication of a previously added attachment
6) Send email and observe the received email does not have the original attachment present