Jango service integration

First functional version of Jango service integration for Nuvola Player 3

Features of previous integration for Nuvola 2 are working: play / pause / thumb up / thumb down / song info and art.
[Use Nuvola.Actions.setState instead of this custom methon](http://tiliado.github.io/nuvolaplayer/development/apps/api_reference.html#Nuvola.Actions.setState)