Gamesetup - Optionally allow players to setup the game

[elexis]

It would be nice if players could pick their own civilizations without having to communicate it via chat to the host.

Since it is a delicate issue to balance the teams, the setting could be implemented using a dropdownlist, giving players different degrees of freedom (none, civs only, civs+teams, all gamesettings)).

---

There is an according TODO in gamesetup.js:

	// TODO: Shouldn't players be able to choose their own assignment?
	for (let i = 0; i < g_MaxPlayers; ++i)
	{
		Engine.GetGUIObjectByName("playerAssignment["+i+"]").hidden = true;
		Engine.GetGUIObjectByName("playerCiv["+i+"]").hidden = true;
		Engine.GetGUIObjectByName("playerTeam["+i+"]").hidden = true;
	}

(Previous releases had signficantly imbalanced civilizations, so no sane host would have allowed players to pick OP civs. With alpha 19, balance is significantly improved, so that this feature becomes actually useful).