add optionnal dependency to pinocchio

CMakeLists.txt

@@ -18,6 +18,10 @@ SET(CXX_DISABLE_WERROR True)
 SETUP_HPP_PROJECT()
 
 ADD_REQUIRED_DEPENDENCY(eigen3)
+ADD_OPTIONAL_DEPENDENCY(pinocchio)
+IF(PINOCCHIO_FOUND)
+  ADD_DEFINITIONS(-DCURVES_WITH_PINOCCHIO_SUPPORT)
+ENDIF(PINOCCHIO_FOUND)
 
 SET(BOOST_COMPONENTS unit_test_framework serialization)