Bunch of changes

- Functional cube movement Initial pass working
- Got rid of jsu/get-prop and extended object to support clojure map functions
- Minor improvement replaced a (first (rest x) ) with (second x)
- Added alpha control
   You can now set a render target's buffer type to have alpha. You can set
   the alpha clear value for a layer as well.
Work towards generalising attributes for fx

I'm badly writing another serialiser aren't I?

Oh well :)