GUIServer ,Button & Extensions

GuiServer Added, not so much implementation. Only methods to calculate
positions in Screen-Space from a predefined Grid.

IButton, interface to implement per each component to wants to work as a
Button.

P8Button, component to attach to any GameObject. P8Button searchs for a
IButton and invokes the specific methods.

Extensions, Extension to Rectangle to resize the rectangle. Extension to
Component to search Interfaces in the way: GetInterfaces<MyInterface>()

Test01 modified to test P8Button. Added ScaleOnPress2.

Nothing else. Congratulations.