vdom.Helper: createDeltas() => ensure there are no move OPs to the same index

[tobiu]

this does not cause any bugs, but triggers a not needed dom OP.

            if (movedNode) {

                // todo: check if there is a real index change

                deltas.push({
                    action: 'moveNode',
                    id      : oldVnode.id,
                    index   : movedNode.index,
                    parentId: movedNode.parentNode.id
                });

[tobiu]

this should also get added to the latest calendar siesta test.