[dialog] Add APIs to set position and dimension

[DiegoCardoso]

Developer could be able to set the coordinates (top, left) and dimension (width, height) of the overlay.

Two things that could be part of this:

• A draggable event after dragging is done
• Update resize event to add the top and left positions to its detail data (the reason is that so, dialog flow could sync these values on resize)

[ado2000]

Hope to see this feature in next release.

[osenbg]

When will this feature available ?

[rolfsmeds]

• We should avoid setting width/height on a postitioned-but-not-sized Dialog to avoid the problem that dragging currently has: Dialog no longer resizes automatically after dragging. #436
• The left/top position should be reflected back to the server when a drag-move ends, so that the getters return the new values and the position can be restored with @PreserveOnRefresh.
• Resize event needs to convey updated top/left coordinates as well.

[TatuLund]

It is possible to set the position using JavaScript, example is found here

https://github.com/TatuLund/mdi-demo/blob/master/src/main/java/com/example/application/components/window/Window.java#L222