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.
if you refer to getCurrentSongName, yes, there are no parameters. I have to call that 3 lines from different places, so I centralized in a function, but I have no need for parameters here.