afterLoad: allow user to execute some action after data is loaded

[avp90]

allow user to execute some action after data is loaded
e.g.

setData: function(data, afterLoad) {
            if (data) {
                this.clear();
                data.forEach(entry => {
                    this.addRow(entry);
                });
                if (typeof afterLoad == 'function') afterLoad();
            }
        }

[torrobinson]

This is actually a good idea, in the case you wanted to only show the editor or perform some logic after the control is "ready" and rows have been loaded in. Thanks. I'll review the other changes when I get some time in the next day or 2

[avp90]

ok, thanks