Function move_ticket 

pub fn move_ticket(
    store: &Store,
    ticket_id: &str,
    to_list: &str,
    position: Option<usize>,
    actor: &str,
    now: DateTime<Utc>,
) -> Result<()>

Move a ticket to to_list at an optional 0-based position (appended if None). Removes it from whatever list currently holds it.