[GRASS-git] [OSGeo/grass] 63f758: Reference CONTRIBUTING.md file in README (#283)

[Vaclav Petras]

  Branch: refs/heads/master
  Home:   https://github.com/OSGeo/grass
  Commit: 63f75826b7e954da79c3c252e0877e7f0778ce1b
      https://github.com/OSGeo/grass/commit/63f75826b7e954da79c3c252e0877e7f0778ce1b
  Author: Vaclav Petras <wenzeslaus at gmail.com>
  Date:   2020-01-15 (Wed, 15 Jan 2020)

  Changed paths:
    M README.md

  Log Message:
  -----------
  Reference CONTRIBUTING.md file in README (#283)