robot in the world.

TODO: add package.xml file.

* Arms have 8 DOF instead of 7 (include last gripper joint)
* include the grippers as a fixed joint

[urdf] Change talos_small.urdf to use the smaller STL meshes.

* depends on urdfdom>=0.2.9. does not depend on Catkin
* remove package.xml
* add submodule cmake

NOTE: ASSIMP is angry with the header of the bigger STL files like arm_1.stl

*talos_small(without gripper),
*talos_full_collision(loading collision geometry)
*talos_full(loading full mesh geometry)

*make talos_description into current package. remove other sub-packages
*Contains srdf file with feet specificities, halfSitting and disabled collision pairs
*Contains urdf file for loading simpler "collision" geometry in visual models.