README: Add link to instructions for publishing the docs

I was looking for these instructions in the README.md file and any other
file in the root folder, but they are in a file somewhere in the folder
structure where they are hard to find.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I251a964a7434022499db3d935ee47c29abdf834e
1 file changed