- removed reference in render.h (really bad, shouldn't include a platform
specific header so widely unless really necessary)
- added M_PI, M_PI_2, M_SQRT, M_SQRT_2 defines to BLI_arithb.h... this is
a better place as it is more the "standard" blender math header. left
in winstuff.h as well for the moment for simplicity
- other changes are patches to code so everything works ok with this
shuffling.