*Disabled ray counter (can be enabled on render/extern/include/RE_raytrace.h by commenting out the define)
*marked bvh_node_merge() as static inline (hopping it now compiles on gcc and mingw)
* Made bvh_node_merge() in svbvh.h static (fix suggested by jaguarandi). This makes mingw link again.
* Also, patched my previous fix for ... = {}; since mingw didn't like the other fix (which was for msvc).
* mingw almost compiles again cleanly, except for a linking error when linking blender http://www.pasteall.org/8297
* win64 should compile again too to a similar degree?
* silenced warnings about no newlines...
(this is a generalization of some of the experimental stuff i tried during SoC,
but only had time to improve a few days ago)
- it should yield slightly better results
- the cost model can somehow be tweaked to optimize for diferent trees.
*cleaned up some code
*added counters for number of SIMD BB tests
*added GPL license block on missing files
