Change character's Y rotation based on velocity.

I’m making a top down puzzle game. You can move the character up down left and right.
The character is moved by changing its velocity (rigidbody.velocity = movement).
The only thing I need to do now is rotate him, I’ve tried LookAt, LookRotation, transform.rotation and SetLookRotation but they all seem to bug out or just not work at all. I just want the characters Y rotation to change based on its velocity, if its moving up, then rotate his Y in that direction.

My Code:
public float speed = 6f;
public GameObject camTarget;

	Vector3 movement; 
	Rigidbody playerRigidbody;

	void Awake(){
		playerRigidbody = GetComponent<Rigidbody> ();

	void FixedUpdate(){


		float h = Input.GetAxisRaw ("Horizontal");
		float v = Input.GetAxisRaw ("Vertical");

		Move (h, v);

	void Move(float h, float v){
		movement.Set (h, 0f, v);

		movement = movement.normalized * speed * Time.deltaTime;

		playerRigidbody.velocity = movement;


	void CameraShake(){
		Camera.main.transform.GetComponent<Animation> ().Play ("CameraDarken");
		camTarget.GetComponent<Animation> ().Play ("CameraShake");

My Character:

Any help at all would be greatly appreciated.

Try putting this right after setting the velocity: