`TruncatedNormal` initializers have been changed to match those in
        external Keras.
    *   Breaking change: `model.get_config()` on a Sequential model now returns
        a config dictionary (consistent with other Model instances) instead of a
        list of configs for the underlying layers.

## Bug Fixes and Other Changes

*   C++:
    *   Changed the signature of SessionFactory::NewSession so that it can