Will Moore

Add robust logging mechanism

1

**What I'd like:** Implement a logging mechanism to improve Updater's logging output in lieu of relying on `log.Printf` statements. Potential candidates: https://pkg.go.dev/github.com/sirupsen/logrus https://pkg.go.dev/go.uber.org/zap

Add mindful draining

2

**What I'd like:** Currently Updater operates under the assumption that it is the only actor manipulating the instances to DRAINING or ACTIVE. In situations where this is not true instance...

Implement managed package refactor

2

> Instead you could create a new type `Instance`, i think which I suggested somewhere else and maintain a list of this type whose items gets modified/deleted/added throught the update...