Scene_Battle::UpdateEvents renders full status window on every frame

[VannevarXbox]

I am currently working on a port to the original Microsoft Xbox, which has been working well so far aside from the framerate getting very low during battles, in the 2k3 test game. I have traced it to this:

bool Scene_Battle::UpdateEvents() {
	auto& interp = Game_Battle::GetInterpreterBattle();
	interp.Update();
	status_window->Refresh();

status_window->Refresh() clears and re-draws the entire status window, which the Xbox has trouble keeping up with when called (almost?) every frame on top of other processing.

Calling status_window->RefreshGauge() instead (depending on Scene_Battle.state) seems to remove this barrier to framerate, which runs at around 60 FPS now (instead of 2-10 FPS before)

I am submitting this as an issue here rather than attempting a pull request at this time, since I'm not yet familiar enough with EasyRPG internal state to determine in what states calling RefreshGauge would be appropriate. However, it does seem to be a potential major bottleneck on slower systems.