Camera controls, fix some math; lighting probably broken

src/math.zig

@@ -1,3 +1,4 @@
+pub const Iterator3 = @import("math/Iterator3.zig");
 pub const Matrix4x4 = @import("math/Matrix4x4.zig").Matrix4x4;
 pub const Quaternion = @import("math/Quaternion.zig").Quaternion;
 pub const Vector2 = @import("math/Vector2.zig").Vector2;