title: javafx tableview detect any change upon any of rows including addition of new one
body: <p>because I don't really know the sollution.
  Lets say i have a TableView that holds info about product: description, quantity and the price. Also have a label that shows a sum of prices (times quantity) of all products from a table. Now i want to be notified about any changes that took affect on this component like changes in existing rows or addition of a new one. Is there any listener or sth similar to achieve it?</p>