DnD w/ beta.2

[gregoryj98]

Some fixes for removing layers DnD on beta.2:
DnD.js
add around line 242 - this.droppedItems[file.name].setLayerIds([ this.createLayerID('csv-' + file.name)])
add around line 336 - this.droppedItems[url].setLayerIds([layer.id]);
edit around line 680 - id:this.droppedItems[filename].getLayerIds()[0]
LayerControl.js
add around line 239 - try {layerControl._scaleRangeHandler.remove();
}catch(err){}