Explicitly list dependencies

The code has an explicit dependency on React's `stream` component and `evenement`, hence we should explicitly define both as a dependency.

Currently, they're (implicitly) installed as part of a dependency of the `socket` component. IMHO this is an implementation detail that we should not rely on.

The resulting dependency graph looks like this:
![graph-composer](https://cloud.githubusercontent.com/assets/776829/3223580/a0eb5a2e-f024-11e3-843e-dae91aa9bd77.png)