CBLT-298:  for jobs that download package files, rename them, and
upload to same S3 location we downloaded from:

    rename_ios_artifacts_master
    rename_ios_artifacts_100

    rename_sgw_artifacts_master
    rename_sgw_artifacts_100

The point is to download packages named -1.0.0-nnnn_ to -1.0.0_
to prepare a release candidate for release.

There will be jobs that take these re-numbered artifacts and
Stage/Release/Undo to S3 location served by www.couchbase.com/download

Change-Id: Ic1f0a8550dbf17c61dbf7bc02d3177d2c02a42f9
Reviewed-on: http://review.couchbase.org/37530
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>