Beautify display of CSS tree renderer for deeper trees
- allow one to specify general UL class via "toc" includelet (was only CSS class for top-level UL) - support passing general class for UL for tree renderer (was only CSS class for top-level UL) - passing properties also via "add_page" to TreeNode instances
- Added native CSS classes for Tree renderer (named "xowiki-tree" to avoid name clashes).
- Made TreeRenderer more configurable, by providing css class names etc.
- toc includelet: replaced default (when no style is provided) from yuitree to list + xowiki-tree. The old behavior can be achieved by {{toc -style yuitree}} Note that not all features of the YUI tree might be available
- The CSS variant with xowiki-tree can also be used for the folder-tree, but so far, the bootstrap3 renderer is more nice.