Robocup 0.1

This pull request is based on [Pull request 1](https://github.com/osrf/robocup_3d_simulation/pull/1), merged with the work that we did on site during Patrick's visit.

This will require a few pull requests from gazebo.

[Pull request 1](https://bitbucket.org/osrf/gazebo/pull-request/1101)
[Pull request 2](https://bitbucket.org/osrf/gazebo/pull-request/1099)