*   `tf.contrib`:
    *   `tf.contrib.distributions`:
    *   Add `tf.contrib.distributions.Autoregressive`.
    *   Make `tf.contrib.distributions` QuadratureCompound classes support batch
    *   Infer `tf.contrib.distributions.RelaxedOneHotCategorical` `dtype` from
        arguments.
    *   Make `tf.contrib.distributions` quadrature family parameterized by