Add aerodynamic drag model for MuJoCo dynamics

[juan-g-bonilla]

Add the equivalent of dragDynamicEffector for MuJoCo dynamics.

[juan-g-bonilla]

Feedback from @schaubh (feel free to add items/correct):

• Rename to a more specific model, not "aerodynamicDrag" but cannoball or another more specific.
• Add an .rst.
• Remove v < 1e-10 optimization. It's overkill and adds a built-in constant.
• Move this to a new folder under simulation called forceTorque (workshop name?). Remove compile-time dependencies on mujoco, add helper functions only through Python (SWIG) (so it becomes a runtime dependency).