Updated Eigen header includes

The eigen3/ prefixed header does not include certain necessary declarations for
EIGEN_USING_STD

source/RobotAPI/gui-plugins/HapticUnitPlugin/MatrixDatafieldDisplayWidget.h

@@ -25,7 +25,7 @@
 
 #include <QWidget>
 #include <QMutex>
-#include <eigen3/Eigen/Dense>
+#include <Eigen/Dense>
 #include <valarray>
 #include <ArmarXCore/interface/observers/ObserverInterface.h>
 #include <ArmarXCore/observers/variant/DatafieldRef.h>

source/RobotAPI/libraries/RobotAPINJointControllers/DMPController/NJointJSDMPController.h

 
 #pragma once
 
+#include <Eigen/Dense>
 
 #include <RobotAPI/components/units/RobotUnit/NJointControllers/NJointController.h>
 #include <VirtualRobot/Robot.h>