catkin: 0.6.7-0 in 'indigo/distribution.yaml' [bloom]

Increasing version of package(s) in repository `catkin` to `0.6.7-0`:

- distro file: `indigo/distribution.yaml`
- bloom version: `0.5.9`
- previous version for package: `0.6.6-0`

## catkin

```
* reset CATKIN_SHELL in devel space generated env.sh files (#652 <https://github.com/ros/catkin/issues/652>, #655 <https://github.com/ros/catkin/issues/655>)
* ignore cd path echo when using CDPATH (#654 <https://github.com/ros/catkin/issues/654>)
* use PYTHON_EXECUTABLE for _setup_util.py (#646 <https://github.com/ros/catkin/issues/646>)
* expose PYTHON_EXECUTABLE to environment hook .em templates (#645 <https://github.com/ros/catkin/issues/645>)
* catkin_prepare_release:
  
    * add --no-push to catkin_prepare_release (#657 <https://github.com/ros/catkin/issues/657>)
    * flush stdin before asking for input (#658 <https://github.com/ros/catkin/issues/658>)
  
```