def users(&callback)
      connection.http(:get, "/room/#{id}.json") do |data, http| # data can be blank on locked rooms
        callback.call(data ? data[:room][:users].map { |user| Firering::User.instantiate(connection, user) } : Array.new) if callback
      end
    end
def users(&callback)
      connection.http(:get, "/room/#{id}.json") do |data, http| # data can be blank on locked rooms
        callback.call(data ? data[:room][:users].map { |user| Firering::User.instantiate(connection, user) } : Array.new) if callback
      end
    end
we perform a request each time so
 1) we always are are up to date with the users currently on the room (even if some left)
 2) we make sure the users are here even if the room was instantiated from a
 /rooms request