Added a selection menu for the next spawn loadout

[ptrstr]

This adds a new button under "Spawn" in the Limbo menu to set the next spawn's loadout. This allows you to set your next loadout for when you'll die rather than killing yourself if you want another gun and not continuing the battle you're currently in. List of issues with the current implementation:

• Might be excessive to check if player is alive on every LocalPlayer update
• You can see the button when you just joined a game. I disabled it for when you're in spectator mode since you can't die but couldn't figure out how for the initial menu.

[yvt]

I like this feature!

• Might be excessive to check if player is alive on every LocalPlayer update

Looks acceptable to me.

• You can see the button when you just joined a game. I disabled it for when you're in spectator mode since you can't die but couldn't figure out how for the initial menu.

Addressed in the review.

[ptrstr]

Added all your suggestions. Also, thank you for the scenario idea. Didn’t think of it. Not sure I implemented the stmp::optional correctly though since either way it’d work.

[ptrstr]

Thanks for the help. Really nice of you to have made this cheatsheet 👍. Do more C than C++ that's why I was so alienated by those std:: and stmp:: types. Fixed it and tested.

EDIT: Don’t merge just yet. Forgot to implement the preview for spectator mode.

[ptrstr]

Added support for spectator mode 👍

[VierEck]

• Might be excessive to check if player is alive on every LocalPlayer update

u can do the check in this function instead which is only called when a killaction packet is received

openspades/Sources/Client/Client_Update.cpp

Lines 783 to 784 in 2d91a3f

	void Client::PlayerKilledPlayer(spades::client::Player &killer,
	spades::client::Player &victim, KillType kt) {

and send the next spawn loadout if victim == localplayer

openspades/Sources/Client/Client_Update.cpp

Lines 812 to 819 in 2d91a3f

	// The local player is dead; initialize the look-you-are-dead cam
	if (&victim == world->GetLocalPlayer()) {
	followCameraState.enabled = false;
	Vector3 v = -victim.GetFront();
	followAndFreeCameraState.yaw = atan2(v.y, v.x);
	followAndFreeCameraState.pitch = 30.f * M_PI / 180.f;
	}

it would have been better to have made an additional dedicated feature branch for this and made the pull request from there instead of master branch.