contributing.md link to docs (#2119)

Symlink `CONTRIBUTING.md` to fern/pages/contributing.md so that it appears as a separate tab next to readme on github.

Authors:
  - Anupam (https://github.com/aamijar)
  - Corey J. Nolet (https://github.com/cjnolet)

Approvers:
  - Corey J. Nolet (https://github.com/cjnolet)
  - Gil Forsyth (https://github.com/gforsyth)

URL: #2119

Author: aamijar

CONTRIBUTING.md

@@ -0,0 +1 @@
+See the contributing guide here https://docs.nvidia.com/cuvs/developer-guide/contributing