as3/uscript update, details in description

- created basic handling of loading & saving options in US via a config
file,
todo yet: we need to cache this config in as3 too
- created basic SkillBar consisting of 5 buttons
- created SkillButton, as SkillBar buttons & Interface to them, so they
are able to hold abilities (currently we have only spells but with the
interface it could be anything later),

hud scaling not yet completed, problem is with cursor position, detailed
here:

http://forums.epicgames.com/threads/983409-AS3-Scaled-hud-amp-mouse-cursor-problem
we dont need custom cursor at all, or we can render it from US
HUD::PostRender()