nk_option_text return value inconsistant

[StewBC]

The nk_option_text return value is inconsistant, based on whether the widget is on- or off-screen.

nk_option_text will return 0 (state), if the widget is not on-screen.
It will return is_active (the widget select state, after processing) when the widget is on-screen.

Instead of returning state when off-screen, it should return is_active. There's no way to know from the call that the reason it is returning 0 is because the widget was off-screen.

The code, I think, should read:
state = nk_widget(&bounds, ctx);
if (!state) return (int)is_active; // this is currently: if (!state) return (int)state;

This will return a "proper" state, whether drawn or not.

Currently, the following code will not work because my_bool will become 0 if the widget is off-screen.
my_bool = nk_option_text(ctx, "bool" my_bool);

With the suggested change, my_bool is only altered if the users alters the state of the widget.

The same holds true for nk_option_text_align