juju/juju — pull request #119 by davecheney (2014-06-18 04:18:14+00:00)
Title: Entity.Tag() now returns names.Tag

Wow. This massive changeset is all just to redefine
```
type Entity interface {
Tag() string
}
```
to
```
type Entity interface {
Tag() names.Tag
}
```
The resulting explosion of `.String()` calls is worse than it looks and will go away in the next PR.