RTS Controller?

I'm just getting into Unity with some friends, we are trying to build the player controls currently. We have our camera script working great (RMB rotates camera on mouse input) but we would like a Runescape/RTS style control for the player. I want the player to move to where ever you left click, I've written this code below but the player will move to where ever the camera is facing, not when you click and the player stops moving after you let go of left click.

 var target : Transform;
 
 function Update () 
 {
     var hit : RaycastHit;
     if (Input.GetMouseButton(0))
     {
      if(Physics.Raycast(Camera.main.ScreenPointToRay(Input.mousePosition), hit, 500))
      {
      var localHit = transform.InverseTransformPoint(hit.point);
      target.Translate((hit.point - target.position) * Time.deltaTime);
      }
      }
 }