PM: Make it easy to distinguish PM created ignore events and tickets manually set to ignore state

[runborg]

As for now a manually ignored event and PM ignored event is not as easy to distinguish
As for now i do not have best way to do this.
But i suspect it could be done by eg adding a "added_by_pm" option in the event or a special pmignore state?
(this later will probably break zino1 clients if its not added into the clients or make the server return state ignored when a "enhanced telnet session" is not enabled in the session or so. )