[bot] Implement n_IsPlayerStreamedIn(...)

bot/net/netgame.cpp

@@ -46,6 +46,15 @@ BYTE byteMySeatID;
 
 bool	bSpawned = false;
 
+//----------------------------------------------------
+// MATCH
+BOOL CNetGame::IsPlayerAdded(PLAYERID playerId)
+{
+	if(playerId >= MAX_PLAYERS) return FALSE;
+
+	return bPlayerSlotState[playerId] != FALSE;
+}
+
 //----------------------------------------------------
 // MATCH
 void CNetGame::SetMyZAngle(float fAngle)