Merge pull request #297 from jcarpent/devel

bindings/python/model.hpp

bindings/python/se3.hpp

src/algorithm/frames.hpp

src/multibody/frame.hpp

src/multibody/joint/joint-free-flyer.hpp

src/multibody/joint/joint-planar.hpp

src/multibody/joint/joint-spherical.hpp

src/multibody/model.hpp

src/spatial/se3.hpp

unittest/finite-differences.cpp

unittest/tspatial.cpp