#3060 Documentation of ttk::frame -padding

[Stéphane Aulery]

If I believe http://www.tkdocs.com/tutorial/widgets.html, the documentation does not specify that it is possible to use multiple values ​​to determine the padding of a ttk::frame widget.

I propose to add the following details to ttk_frame.n manpage:

- a single number specifies the same padding all the way around;
- a list of two numbers lets you specify the horizontal then the vertical padding;
- a list of three numbers lets you specify the left, vertical, and right padding, in that order;
- a list of four numbers lets you specify the left, top, right and bottom padding, in that order.