* Add a build info metric
Add a standard Prometheus build info metric to make monitoring rollouts
easier.
* Update prometheus vendoring.
* Fix build error
Fix missing bool in builtinMetricMaps.
Signed-off-by: Ben Kochie <superq@gmail.com>
This commit implements a massive refactor of the repository, and
moves the build system over to use Mage (magefile.org) which should
allow seamless building across multiple platforms.