Blender Git Loki

Fix second part of T41068 -- reflection mapping was wrong

Few things:
- reflect() takes arguments in this order: N, I, it was swapped
in the previous code for some reason.

- Normal and view vectors are to be normalized. For the view
vector we're now using shade_view() in order to deal with the
ortho camera. However, Cycles does not support ortho camera
for reflection, but this is easy to do in a separate commit.

- Reflection vector is to be in the world space. Kudos to
Antony Riakiotakis for figuring this out!