Still implementing GameUI, i don't like that we do not delete objects from vectors and that they do not deallocate memory.

I found vector.shrink_to_fit() function, which I think should be use
after clearing vector (it makes vector shrink to number of elements in
it, so after clearing it decreases to 0).

And since after changing or pushing the new state we initialize it, i
think we should destroy everything while cleaning (like all the menus)
correct me if I'm wrong