feat(daemon) `ipfs daemon --initialized`

With this PR, users can fetch and run ipfs in _one_ command.

```
docker run -d -p 4001:4001 -p 5001:5001 jbenet/go-ipfs daemon --initialized
```

Magic.

nb: needs https://github.com/jbenet/go-datastore/pull/9
In this case the concern is around sound composition.

Typically the wrapping object is in control of the objects of which it is composed. When the public close method is delegated to composed object. 

Refactoring is more difficult because you need to worry a lot about side effects. The context closer doesn't provide clear semantics around it's responsibilities. While it's still being fleshed out, it ought to be used judiciously.