Change name of type

src/Mathematics/FootConstraintsAsLinearSystemForVelRef.cpp

src/Mathematics/FootConstraintsAsLinearSystemForVelRef.h

src/Mathematics/PLDPHerdt.cpp

src/Mathematics/PLDPSolverHerdt.h

src/ZMPRefTrajectoryGeneration/ZMPVelocityReferencedQP.cpp

src/ZMPRefTrajectoryGeneration/ZMPVelocityReferencedQP.h

src/ZMPRefTrajectoryGeneration/generator-vel-ref.cpp

src/ZMPRefTrajectoryGeneration/generator-vel-ref.hh

src/privatepgtypes.h