[Watch] Add support for Properties and Methods

[mrbeardy]

Feature: Watch
Description: Allow the [Watch] Attribute to be used on Properties and Methods.
Why?: As well as increasing the amount of things that can be watched, allowing Properties and Methods to be read and invoked will remove the need to set temporary variables to Watch an inherited field.

Before

class Box : MonoBehaviour {
  [Watch] private Vector3 position;

  private void Update() {
    position = transform.position;
  }
}

After

class Box : MonoBehaviour {
  [Watch] private Vector3 Position => transform.position;
}

[Watch] on Method

class Box : MonoBehaviour {
  [Watch]
  private Quaternion GetRotation() {
    return transform.rotation;
  }
}