Disable in-game HUD for now

Need to sort out the problems with dispatching events to the HUD or the gamemap, respectively.
Disabling the HUD for now so it should be possible to interact with the map in case someone
wants to work on its rendering.

src/play_controller.cpp

@@ -307,7 +307,8 @@ void play_controller::initialize_and_show_ui()
 	ui_.reset(new gui2::dialogs::game_ui());
 	assert(ui_);
 
-	ui_->show(true);
+	// TODO: reenable once we get the HUD/map event separation problems sorted out...
+	//ui_->show(true);
 }
 
 void play_controller::reset_gamestate(const config& level, int replay_pos)