• optimize non-optimized with SIMD vec4 operations with SSE/SSE2
• add one and zero helpers for vectors
• fix scale_as for zero length vector: now it it returns zero
• new functions for vec3 and vec4: (s suffix stands for scalar)
  • _mul: multiply two vector (replacement for _mulv)
  • _div: div two vector
  • _divs: div vector with scalar
  • adds: add scalar to each components of vec
  • subs: sub scalar from each components of vec
  • addadd, subadd, muladd, muladds helpers ( += )
• optimize rotate vec3 using matrix4, add same function for mat3
• add some tests for vectors
• update docs for new apis