Changed frontend application

Hello, I have taken the liberty to develop a single page application that exposes all the API available in the Spark JobServer. It can be used as a drop-in replacement for the current jQuery app, but also covers creating and deleting contexts, launching jobs, checking the results and uploading jars.

The source can be found under

https://github.com/unicredit/spark-jobserver-frontend

Here I have put the compiled version. Check if you think it can be good for you, and let me know if you think I should make any improvement.

If you are interested in how it was developed, I used Facebook React and CoffeeScript, with Bootstrap for the CSS and a few other libraries.