[borinot] Added quadrotor + 2dof arm robot

python/example_robot_data/robots_loader.py

robots/borinot_description/README.md

robots/borinot_description/meshes/borinot__base_link.dae

robots/borinot_description/meshes/flying_arm_2__link1.dae

robots/borinot_description/meshes/flying_arm_2__link2.dae

robots/borinot_description/meshes/propeller_ccw.dae

robots/borinot_description/meshes/propeller_cw.dae

robots/borinot_description/urdf/borinot_flying_arm_2.urdf