Add a action to ticket history

RT: 3.4.5

Some of our requestors forget or loose the email messages sent to them
regarding their ticket. I’d like to add a [Send Again] action link next
to the [Show] link on the Outgoing message recorded history line.

If such a contribution or patch exists and I missed it on the wiki,
please let me know. Otherwise if you have some ideas, I’m willing to do
a little coding to make it work.

Thank you,