Replace robot_pose_ekf with robot_localization.
small fix
Merge pull request #13 from g/add-robot-localization

Replace robot_pose_ekf with robot_localization.
Merge branch 'indigo-devel' of https://github.com/g/grizzly into remove-properties
A few more tidy-ups here.

- More joints to after their respective child links.
- Group wheels together at the end.
- Re-add IMU orientation.