genmsg: 0.5.6-0 in 'indigo/distribution.yaml' [bloom]

Increasing version of package(s) in repository `genmsg` to `0.5.6-0`:

- upstream repository: git@github.com:ros/genmsg.git
- release repository: https://github.com/ros-gbp/genmsg-release.git
- distro file: `indigo/distribution.yaml`
- bloom version: `0.5.12`
- previous version for package: `0.5.5-0`

## genmsg

```
* fix interpreter globals collision with multiple message templates or modules (#53 <https://github.com/ros/genmsg/issues/53>)
```