put Pause GUI into own class
put WinLoseGUI into own class

also added Utilities method to draw a screen centered texture
moved GUI classes to the GUI folder
put bilance into own GUI class

added GameGUI prefab
put credits GUi into own class

added players field to GameController so all classes can reference that.
put currently selected overlay into own class

added tag for GUI
added ActionSlots property in GameGUI
own class for action denied and cooldown GUI

added ActionInvoker to handle the cooldown