Created a session service to handle the copy event

@fiallega @znja completed the session service and copy event. please take a look.
@znja @malads 
You don't need accessor functions. Here you will have:
this.insertEvento = eventoService.eventoInstance();
That is it.
In the controllers to make use of it you will have
$socpe.evento = sessionService.insertEvento;
And from this point on, you play with $scope.evento. For example if you want to initialize it you do
$scope.evento = eventoService.eventoInstance()
which would also change the insertEvento in the sessionService