Nikhil Agarwal

In order to allow seeing PDF layers and toggling them on/off, I am wondering what would be the best way to add support for OptionalContentConfig in this library. See https://github.com/mozilla/pdf.js/issues/269#issuecomment-669282999...

The purpose of this change is:- - Add onLoad prop to be notified when pdf document has loaded - Allow custom highlight color for text and area highlights