Added draw_sprite_padded and GPUprof upd.

-Added draw_sprite_padded that allows drawing a sprite, like a button or
a background of a window. You select the top, left, right and bottom
padding that will be the border and the middle will scale with the size.
It's useful for functions to draw buttons, menus, windows and other GUI
elements. And it's the basis of the basic GUI extension.
-More profiler progress.