Gson type adapters can be registered as Dagger set bindings.

Now you can register more custom gson types by adding to the set binding for `TypeAdapter`.

ex.

```java
@Provides(type = Provides.Type.SET) TypeAdapter upperZone() {
  return new TypeAdapter<Zone>() {

    @Override public void write(JsonWriter out, Zone value) throws IOException {
      throw new IllegalArgumentException();
    }

    @Override public Zone read(JsonReader in) throws IOException {
      in.beginObject();
      Zone zone = new Zone();
      while (in.hasNext()) {
        zone.put(in.nextName(), in.nextString().toUpperCase());
      }
      in.endObject();
      return zone;
    }
  };
}
```