Adding backward compatibility for 0.6 clients. They cannot join games with > 7 players.

src/net/common/servergamestate.cpp

@@ -308,6 +308,11 @@ ServerGameStateInit::HandleNewSession(ServerGameThread &server, SessionWrapper s
 		{
 			server.MoveSessionToLobby(session, NTF_NET_REMOVED_GAME_FULL);
 		}
+		// Check whether the client supports the current game.
+		else if (curNumPlayers >= session.sessionData->GetMaxNumPlayers())
+		{
+			server.MoveSessionToLobby(session, NTF_NET_NEW_RELEASE_AVAILABLE);
+		}
 		else
 		{
 			if (session.playerData->GetUniqueId() == server.GetAdminPlayerId())