Room rental period increase, fix 'user entered' NPC text, change Insignia quest to favor blank Herald Shields over dedicated ones.

Rented rooms now added to room count statistics when created. Normally this list only holds rooms added during RecreateAll. A new message in statistics.kod, "AddToRoomCount()", has been added to handle this and is called when the room is created (from rntmaint.kod).

Room max rental period upped to 120 real world days from 20. 20 days was far too short and frequently bites people who go on holiday, have real world things to attend to or just forget to pay for a few weeks.

Users entering a room now cause UserEntered() to be sent to all monsters, so NPCs can say the appropriate text if necessary. A lot of resources were present in NPC files which should be called when a user enters, but nothing actually sent the UserEntered() message to trigger this.

Modified AwardPrizeOrPenaltyInsignia in questnode.kod (called on completion of insignia quest) to favor blank heralds over already dedicated ones. If you have more than one shield and one is undedicated, it will use that one for the new insignia instead of the first one it finds. Uses the first blank herald it finds but will still overwrite insignias if there are no blank heralds available. Still defaults to the shield the player is wearing.