set_end_child
Description:
Sets the end child of this to child.
If child is `NULL`, the existing child will be removed.
Parameters:
| this | a `GtkPaned` | 
| child | the widget to add | 
Sets the end child of this to child.
If child is `NULL`, the existing child will be removed.
| this | a `GtkPaned` | 
| child | the widget to add |