Improve deterministic ImageNet baseline

[dustinvtran]

@dustinvtran
I'm thinking of efficientnet or assemble-resnet. Both have TF implementations:

• https://github.com/clovaai/assembled-cnn
• https://github.com/tensorflow/tpu/tree/master/models/official/efficientnet/tpu (which I believe is still in the process of converting to Keras/TF 2.0)

google/edward2#207

[dustinvtran]

We've had EfficientNet for a few months now. However, there are difficulties still reproducing at least as good the accuracy numbers of the EfficientNet paper due to TF2/Keras/CTL. IIRC, Hieu Pham, TF Model Garden, and an intern are working on this.

[dustinvtran]

Duplicate issue: google/edward2#269.