Currently, there's an interface defining a DiscoItem object. There's no implementation of it, other than in-line implementations in methods (the same goes for the sub-interface, DiscoServerItem). Where manipulations of DiscoItem objects are done, Dom4J Element instances are used instead. The DiscoItem interface has been replaced by an implementation of that interface (again, same goes for the sub-interface, which is now a subclass). As I assumed there would not be other implementations of the same interface (which would give you 'another kind' of DiscoItem objects, but what's the point?), I removed the interface completely.

As a result of the changed representation, the DiscoItemsProvider interface now declares a method that returns an Iterator of DiscoItem objects, instead of Elements. This caused changes in a number of classes.

Result Set Management functionality has been added, which causes all disco#items request to be result set managable (this is, for instance, useful for large listings or MUC rooms).

git-svn-id: http://svn.igniterealtime.org/svn/repos/openfire/branches/rsm@9166 b35dd754-fafc-0310-a699-88a17e54d16e