Predator manipulator collision

[bsb808]

From PR#42

Collision = visual. No individual collision models with reduced textures was produced. ∴ , which may result in more collision computations than needed.

The visual mesh is fairly simplified, so this may not be an issue in terms of computational load. Should evaluate before generating new collision mesh.

[bsb808]

I tested by running the default example:

roslaunch uuv_dave uuv_dave.launch

and the Predator example described here: https://github.com/Field-Robotics-Lab/dave/wiki/Swapping-out-the-Oberon7-arm-with-another-manipulator

There was no noticeable difference in RTF or FPS. If it ain't broke, don't fix it!

Please re-open if this becomes and issue.