v0.6
Better support for rebasing reviews This change improves the support for rebasing reviews in multiple ways: 1. Adding a new `refs/archives/devtools` ref that can be used to make sure that commits which have been rebased do not get garbage collected. 2. Adding a new `alias` field to the request schema that enables tracking review history across rebases. 3. Adding a new `rebase` subcommand that enables us to update the history for a change prior to submitting it.