Release v0.3.2

Changes since v0.3.1:

• [Python] Fix binding of Piecewise.curve_at_index
• Replace several critical asserts with exceptions
• Install the header python_definitions.h in include/python
• Add python API to retrieve bezier waypoints as 2D array
• Add C++ and python API to retrieve the translation or rotation curve contained in a SE3 curve
• Correctly specify the corresponding shared_pointer to all python class
• Fix SO3 constructors when t_min == t_max
• Correctly check and raise error when trying to use polynomial constructors from boundary condition when t_min == t_max
• Reworking of the exposition of the abstract class in Python (fix https://gepgitlab.laas.fr/loco-3d/curves/issues/32)
• Correctly register the shared_pointer of the base abstract classes in boost::Python