Don't bake DrawcallTreeNodes too early, just copy children across.

* Fixes markers within deferred contexts from not showing their children
  in the event browser (although they would still replay the events)
Add a macro (that is default on) to include win8 sdk dependency

* Disabling the macro means that the DirectX SDK (June 2010) should be the
  only dependency and you can compile as normal, just without d3d11.1
  support.
* This won't be massively supported and official releases will not use this
* It might break in future as I won't be testing, it might even be deleted
  to tidy up, but until then it might come in handy for some.