Feature Request - Enhance Reject Ticket filter actions

[ml247]

Introduce a function to change the message that appears when the "Reject Ticket" filter action is invoked.
Presently it says something like "Only authorized users can create tickets" in an alert bar at the top of the screen.
But it would be useful if we could change this because we would use it to alert the agent that the client was a poor payer or something like that.