Add move_to_pose_server and iiwa_msgs package with service definition

- Implement move_to_pose_server for motion planning using MoveIt
- Create iiwa_msgs package with MoveToPose service definition
- Update iiwa.launch.py to include move_to_pose_server node
- Modify joint_limits.yaml to add position limits for joints
- Remove iiwa_voice package and related files

src/iiwa_planning/scripts/motion_planning_test.py

@@ -78,7 +78,8 @@ def main():
     pose_goal.pose.position.x = 0.28
     pose_goal.pose.position.y = -0.2
     pose_goal.pose.position.z = 0.5
-    iiwa_arm.set_goal_state(pose_stamped_msg=pose_goal, pose_link="link7")
+    iiwa_arm.set_goal_state(pose_stamped_msg=pose_goal, 
+                            pose_link="patron")
 
     # plan to goal
     plan_and_execute(iiwa, iiwa_arm, logger, sleep_time=3.0)