Update way to dispatch events

Use the old way of creating event to be IE11 compatible.
See https://developer.mozilla.org/en-US/docs/Web/Guide/Events/Creating_and_triggering_events
Use polyfill addEventListener
Keep ref of img element before removing it from the DOM
Add quick-crop feature to the crop plugin

Squash of commits:

- aed7300 Crop with key : improve deal with ratio constraint
- 4acbefa Add quick crop with "c" keypress
Build GH pages