operator == : in child class, try to cast 'other' to the child type to perform the correct operation, before falling back to the curve_abc operator

Topic/piecewise generic

Fix optional dependency to pinocchio for python bindings

[Python][Tests] remove all unecessary reshape(-1,1) in python

[Python] correctly define eigenpy matrix type for point3 and point6

Solve #19

solve #29

[CMakeList] replace hardcoded name for installation path with $PROJECT_NAME

fix hardcoded path, fix https://gepgitlab.laas.fr/loco-3d/curves/issues/22

[CMakeList] fix install path of optimization files

[Tests][Python] use Quaternion.isApprox to test equality instead of ==

Fix all compiler warnings