Notebook widget with close page button

[Dawid Zamirski <dzrudy gmail com>]

Hello

I'm just starting with Gtk programming, and I would like to know how to 
make a little close "x" button on each page of a notebook widget 
(simillar to the one in gedit when working on multiple files). Does it 
require to build a custom wigdet that inherits from orginal notebook 
widget? Thanks