bwi: 0.2.1-0 in 'hydro/distribution.yaml' [bloom]

Increasing version of package(s) in repository `bwi` to `0.2.1-0`:

- distro file: `hydro/distribution.yaml`
- bloom version: `0.5.7`
- previous version for package: `0.2.0-0`

## bwi_desktop

- No changes

## bwi_desktop_full

```
* bwi_desktop_full: add python-bloom, remove openni_tracker (#9 <https://github.com/utexas-bwi/bwi/issues/9>)
* Contributors: Jack O'Quin
```

## bwi_launch

- No changes