support for more than one grid

[dhagan]

Any pointers on what I would need to do to support two or more grids, dragging between the two instances - similar to http://troolee.github.io/gridstack.js/demo/two.html?

[dhagan]

vm.options = {
cellHeight: 200,
verticalMargin: 10,
acceptWidgets: '.grid-stack-item'
};