make openmp work with icc
Braces
Fix MSC version in the manual
MSVC-compatible inline
MSVC-compatible SSE2
Merge branch 'master' into msvc

* master: (27 commits)
  MSVC-compatible SSE2
  MSVC-compatible inline
  Fix MSC version in the manual
  Braces
  make openmp work with icc
  Use log to give more information about invalid uses of the library
  mention output option
  Workaround for saving chunks in old libpng versions
  use gAMA and cHRM to build RGB profile
  PNG_COLOR_MASK_COLOR
  SSE3 -> SSE2
  Preserve unknown chunks
  Try to avoid OpenMP overhead
  Use LCMS cache when a single thread is used
  Added OpenMP to LCMS code
  Ensure 1-file chunks when using file-based parallelism
  Mark static schedule for OpenMP where appropriate
  Free rwpng images inside rwpng.h
  Braces
  Use gAMA chunk only if sRGB is absent
  ...
Added braces around initializers