MB-6972:  write URL same as non-default S3 ROOT in sources and repo files

Change-Id: I957b99120d484d896509da6e999f781b4523746d
Reviewed-on: http://review.couchbase.org/41159
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>