ur_simple_control

a lot happened. i think i got the structure for the single arm and force-torque sensing on the single arm right. next up is doing the same for dual arm WHILE READING and updating clik functionality. parts of clik need to be renamed cartesian_space, split into point to point and trajectory following, while the other parts need to be split into compliance. same goes for compliant joint space stuff. if some of these are in examples, they need to be moved into the library proper. then mobile base, then the challenge stuff