Bug - MarkTicketSeenUnseen feature can't be filtered by ACL

[BuilderNSV]

Environment

• Server OS: Linux
• Browser: Firefox
• Znuny version: 7.1.3

I think the integration of the Mark As Seen/Mark As Unseen feature was missing some settings out of the box to manipulate with ACL lists.
I want to hide Mark As Seen/Mark As Unseen menu items from ticket menu in AgentTicketZoom and AgentTicketStatusView (Medium, Large views).

1. I can't select AgentTicketMarkSeenUnseen action when construct PossibleNot condition in 'Change settings' section
   I think this action should have been added to "ACLKeysLevel3::Actions###100-Default" setting in Ticket.xml

2. Settings in Znuny.xml
   "Ticket::Frontend::MenuModule###001-MarkTicketUnseen"
"Ticket::Frontend::MenuModule###001-MarkTicketSeen"
"Ticket::Frontend::PreMenuModule###442-MarkTicketUnseen"
"Ticket::Frontend::PreMenuModule###442-MarkTicketSeen"
   should have Item "Action" set to AgentTicketMarkSeenUnseen instead of empty

[BuilderNSV]

Additionally releated to MarkTicketSeenUnseen feature:
'Mark as seen' sentence is missed in translation files.