add .rosinstalls for the muffin indigo workspace

here's the current muffin indigo workspace setup as it is now running on robot10 (and shortly will on robot11)
It looks a bit weird to clone the release repo. I think you should use this instead:

    - git: {local-name: stacks/ivcon, uri: 'https://github.com/ros/ivcon.git', version: master}

(or `version: 0.1.4`, but I like `master` better because it's a branch, not a tag).