Change string orientation to boolean vertical (default false = horizontal).
Merge pull request #4 from AdrianVasiliu/list-dev

Simplify structure of DOM (avoid useless extra DIV); support "height" only as style attribute
Merge branch 'master' into list-dev
Update List CSS style to take into account the new ScrollableList
implementation.
Removes unused style from List.css
Fix List CSS for the new ScrollableList mixin.
Various code and doc cleanup/fix/simplification/refactoring