Add support for AppOptions

[sbutlerjr]

Add support for the AppOptions (https://github.com/Servoy/svyPDFViewer/blob/master/pdfviewer/pdfJsViewer/pdfjs_2.9/web/viewer.js#L46-L208) so that options can be customized without forking the core viewer JS. It would allow setting permissions (printing, downloading, etc) as well as printResolution.

Example usage setting the printResolution AppOption

document.addEventListener('webviewerloaded', function() {
  PDFViewerApplicationOptions.set('printResolution', 300);
});