Code review comment for lp:~zorba-coders/zorba/get-namespace-bindings

Ok, I moved NsBindings to zorba:: scope (in item.h), and changed createElementNode() to also use it (and clients of createElementNode() to use it also).

I've changed the usages of createElementNode() in non-core modules as well, but they compile fine without changes (confirming backwards-compatibility). I'll propose them for merging individually once this change is on the trunk.