stores seating arrangements
| Column Name | Type | Properties | Docu |
| seatplanid | seq32 | Primary-Key | |
| roomid | string:64 | NULL-able Foreign-Key=room(roomid) | the room this seating arrangement belongs to |
| name | string | NULL-able | display name of the seating arrangement |
| plan | text | NULL-able | XML representation of the seating arrangements |
| flags | string | NULL-able | filter flags: defines who can use this arrangement for new events (ignored once it is attached to an event) |