When mail notifications fail or the mail queue is not flushing, it is often not realized until an user notifies the JIRA admin. This can be hours before something like this is noticed by anyone.

We should implement a notification for when the mail queue is not sending out.

Thoughts on how to do this:

• Maybe a notification on top of administration menus (similar to the index suggestions)
• Maybe just a mail queue counter that is easily visible for admins, this way they'll know when the queue is piling up and higher than usual