update pdf loader
remove float from styles when printing html

Added support for image printing in Firefox

Refactored es6 modules.
Support image printing in Safari

Updated module export

Added ES6 Modules
Support for text-decoration and page-break when printing html

added null check on children elements when collecting styles

use image.onload for chrome only
replaced browserify with webpack

fixed image print blank preview

Use require instead of import for modules.

Added font_size parameter (html, json)