ros_control: 0.8.1-0 in 'indigo/distribution.yaml' [bloom]

Increasing version of package(s) in repository `ros_control` to `0.8.1-0`:

- distro file: `indigo/distribution.yaml`
- bloom version: `0.5.9`
- previous version for package: `0.8.0-1`

## controller_interface

- No changes

## controller_manager

- No changes

## controller_manager_msgs

- No changes

## controller_manager_tests

- No changes

## hardware_interface

- No changes

## joint_limits_interface

```
* Use upstream liburdfdom-dev package.
  Refs ros/rosdistro#4633 <https://github.com/ros/rosdistro/issues/4633>.
* Contributors: Adolfo Rodriguez Tsouroukdissian
```

## ros_control

- No changes

## rqt_controller_manager

```
* Register plugin under a group. Fixes #162 <https://github.com/pal-robotics/ros_control/issues/162>.
* Contributors: Adolfo Rodriguez Tsouroukdissian
```

## transmission_interface

- No changes