Update model after an action on an item

[hbcarlos]

Updates model after moving/resizing an item. Implements removing an item. Improves the code base with the following:

• The layout handles the grid and grid items.
• The view listens for changes in the model and applies them to the layout.
• The view listens for changes in the layout and applies them to the model.

[github-actions[bot]]

:point_left: Launch a Binder on branch _hbcarlos/glue-lab/moveresize

[martinRenou]

@hbcarlos is it ready for review?

[hbcarlos]

yes