message: Improve tf.math.l2_normalize documentation
diff: @@ -646,6 +646,22 @@ def l2_normalize_v2(x, axis=None, epsilon=1e-12, name=None):
  For `x` with more dimensions, independently normalizes each 1-D slice along
  dimension `axis`.
  + * 1-D tensor example:
  + >>> x = tf.constant([3.0, 4.0])
  + >>> tf.math.l2_normalize(x).numpy()
  + array([0.6, 0.8], dtype=float32)
  +
  + * 2-D tensor example:
  + >>> x = tf.constant([[3.0], [4.0]])
  + >>> tf.math.l2_normalize(x, 0).numpy()
  + array([[0.6],
  + [0.8]], dtype=float32)
  +
  + >>> x = tf.constant([[3.0], [4.0]])
  + >>> tf.math.l2_normalize(x, 1).numpy()
  + array([[1.],
  + [1.]], dtype=float32)
  +
  Args:
  x: A `Tensor`.
  axis: Dimension along which to normalize. A scalar or a vector of
  