"widthIncludesScrollbar" parameter to handle scrollbar inside the container

I think it would good to determine whether a scrollbar width should be included into `width` parameter or not.

`widthIncludesScrollbar == true` means the scrollbar will not widen a wrapper and the wrapper will always have specified width by the parameter. The wrapper will contain table element of (`width` minus scrollbar width) width. The header will be of `width` width.

Also works if `width` is `null`.