* add a XML dumping routine ( XHTML? )

* the remove() methods need to do various clean-ups, or decide not to:
	+ removed Links should remove corresponding Aliases
	+ removed Categories should recursively remove its elements
	+ removed Aliases should remove ALIASID from target Link
	+ should all of this be handled in DESTROY anyway?

* a bookmarks file diff routine (not just a text diff) would
be nice.

* add support for other formats (like IE, Opera, iCab)
