Add destroy method

Hi.

I try to change the format on the fly. There are two options I tried:

picker.set ({ format: 'dd.mm.yyyy' });

does nothing and there's no way to destroy and recreate the component (see https://jsfiddle.net/vxbfy0ob/2/). I also want to change the labels text so a destroy method is very important, escpecially when you think of a geater app which needs to free resources.

Cheers.