sets the number of rows for the grid
webix.ui({
view:"dashboard",
gridColumns:4, gridRows:3,
cells:[
{ view:"panel", x:0, y:0, dx:1, dy:1, body:{ template:"Single"}},
{ view:"panel", x:1, y:0, dx:2, dy:1, body:{ template:"Wide"}}
// more cells
]
});