Support displaying documents online

[cliffparnitzky]

A nice feature would be to display the file of an document online.

Maybe the usage of viewerjs.org (GitHub: kogmbh/ViewerJS) would make it easy.

[cliffparnitzky]

Another idea could be using the Google Documents' Viewer: http://stackoverflow.com/questions/27957766/how-to-render-word-documentdoc-docx-in-browser-using-javascript

[cliffparnitzky]

Another library: https://mozilla.github.io/pdf.js/