URBNG-137 - [WP] implement sending answer to server

URBNG-153 - [WP] Use GameAuthorizationService in GameWebService (implemented CredentialsService)
URBNG-153 - [WP]Implement api communication for games (join/leave implemented)
URBNG-153 - [WP]Implement api communication for solutions (sending abcd and gps solutions - without receiving points and result)

Also:
* fixed GameAuthorizationService
* fixed GamesListView
* removed unnecessary columns in Game
* added CharId in IABCDPossibleAnswer
* blocked sending ABCD solutions without selected answer(s)