message: docu: updated news
diff: News, Updates, and Announcements
  ================================
  +Feb 3, 2019: Version v0.8.1 now released on GitHub
  +--------------------------------------------------
  +
  +New release version 0.8.1 is now available on the [Open Image Denoise
  +GitHub page](https://github.com/OpenImageDenoise/oidn/releases/v0.8.1).
  +
  Jan 29, 2019: Version v0.8.0 now released on GitHub
  ---------------------------------------------------
  