hg: jdk9/sandbox: 8182029: Make the top-level docs index.html to a HTML-level redirect to the API overview page

[chris.hegarty at oracle.com]

Changeset: 35f50e9952e4
Author:    mchung
Date:      2017-06-13 10:44 -0700
URL:       http://hg.openjdk.java.net/jdk9/sandbox/rev/35f50e9952e4

8182029: Make the top-level docs index.html to a HTML-level redirect to the API overview page
Reviewed-by: alanb, erikj, ihse

! make/Docs.gmk