gistfile1.cs

//This method goes in your character controller
//CharacterController.cs
void GlueToFloor ()
{
  if (Mathf.Abs (move) > 0 || !groundHit || IM.Jump_Button ()) {
  	this.transform.GetComponent<Rigidbody2D> ().isKinematic = false;
  }
  else if (groundHit && Mathf.Abs (move) == 0 && !isPlatform) {
  		this.transform.GetComponent<Rigidbody2D> ().isKinematic = true;
  }
}

//Implemented a new extension to check when character touches a platform
//Collision2DExtensions.cs
public static class Collision2DExtensions {
	public static bool WithPlatform(this Collision2D self) {
		return self.gameObject.tag == "Platform";
	}
}