Small error in angles docstring
Small error in angles docstring

Juanlu001/poliastro,anhiga/poliastro,newlawrence/poliastro,poliastro/poliastro,newlawrence/poliastro,anhiga/poliastro,anhiga/poliastro,Juanlu001/poliastro,Juanlu001/poliastro,newlawrence/poliastro