Initial infra design project config

This is a prototype that started with project_mgmt/project.proto,
trimmed it down a bit to focus on key concepts, then brought in the
concept of build-targets and branches that are tied to the design
project.

The expectation is this will eventually drive CI for factory/firmware,
but also provide accessible config for analysis (e.g. what devices share
what firmware branches, ...).

For release milestones, they will include targeted designprojects, which
will then tie the system build target info, which will then track the
branch defined by the milestones themselves.

Change-Id: I00952042e26fca8e9464cd7ea567927abfe42c71
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/2400918
Tested-by: C Shapiro <shapiroc@chromium.org>
Reviewed-by: David Burger <dburger@chromium.org>
Commit-Queue: C Shapiro <shapiroc@chromium.org>
Auto-Submit: C Shapiro <shapiroc@chromium.org>
4 files changed