Support pinchend event

[johannesjo]

It would be nice, if there would be support for this too.

[zhengjin]

I want to know how to distinguish between pinchin and pinchout events.
This config is not working.
hammerDefaultOptsProvider.set({ recognizers: [ [Hammer.Pinch,{ event:'pinchin', enable:true, time:50}, ['pinch']] ], touchAction: 'pan-y' });