add browser support

[pablomaurer]

Now I do not really like to use a native wrapper for creating a pdf, but there where problems in all other solutions.

• jsPDF
  • html2pdf was very blurry or made only one page (took canvas screenshot..)
  • Tried other way's but then it crashed due memory issues when using images
• pdfmake
  • crashes everything on IOS9 #935
  • Don't really like how we have to build the pdf, html is a lot easier =)

Maybe we could somehow use jsPDF or another lib to generate the PDF in the browser platform. Since it would be cool to have a working solutions for all platforms.