Basically two simple changes, changes, I pulled in the faster
ghash in bmesh (which uses mempools for allocation, providing
a substanstial speedup in some cases, and also I inlined some
of the functions), and I changed __inline to __forceinline for inlining
of math functions.
I also removed the timer in the view3d zoom op (ctrl-middlemouse)
that was making it nonfunctional. Why was that there?
* inline some more functions, from math_base and math_vector
* also made some changes to the way inline is done so it can
work for more than one file
* reflect_v3_v3v3 requires input vectors to be normalized now.
* added rgb_to_grayscale
* added zero_v4, copy_v4_v4, swap_v4_v4, is_one_v3
* added box_clip_bounds_m4 to clip a bounding box against a
projection matrix
