[Issue #24] Last commit of Basic events subsystem (BES)

+ ListenObjects - set of game and step objects
+ a new API call /games/{gauid}?mode=listen
+ a new method to MyListener - waitAnyEvent()
+ a new method in Game service - listenGameAsync
- removed obsolete variable event in the getAsyncGameLastStep
m game.state can only has open, game and close values, all other information should be set to resolution field.