Expose ability to adjust the cloned node before generating image.

[IDisposable]

Added the ability to specify a call-back to be invoked on each node as we clone them so you can adjust the nodes in any way needed before the conversion. The handler is passed in the options as adjustClonedNode which is a function that gets the original node, the cloned node, and a boolean that says if we've cloned the children already (so you can handle either before or after)

Sample use (with this package source inlined) in the fiddle:

const adjustClone = (node, clone, after) => {
  if (!after && clone.id === 'element') {
    clone.style.transform = 'translateY(100px)';
  }
  return clone;                   
}

const wrapper = document.getElementById('wrapper');
const blob =  domtoimage.toBlob(wrapper, { adjustClonedNode: adjustClone});

Also bumps dev packages up to current and cleaned a bit of lint.

Fixes #163

[IDisposable]

Released in https://github.com/1904labs/dom-to-image-more/releases/tag/v3.3.0

Thanks for your contribution @wyking1997!

[wyking1997]

Thank you for your quick support!