add ur_description, fix #7

CMakeLists.txt

example_robot_data/__init__.py

example_robot_data/__main__.py

example_robot_data/robots_loader.py

unittest/test_load.py

ur_description/launch/ur10_upload.launch

ur_description/launch/ur3_upload.launch

ur_description/launch/ur5_upload.launch

ur_description/launch/view_ur10.launch

ur_description/launch/view_ur3.launch

ur_description/launch/view_ur5.launch

ur_description/meshes/ur10/collision/base.stl

ur_description/meshes/ur10/collision/forearm.stl

ur_description/meshes/ur10/collision/shoulder.stl

ur_description/meshes/ur10/collision/upperarm.stl

ur_description/meshes/ur10/collision/wrist1.stl

ur_description/meshes/ur10/collision/wrist2.stl

ur_description/meshes/ur10/collision/wrist3.stl

ur_description/meshes/ur10/visual/base.dae

ur_description/meshes/ur10/visual/forearm.dae