Removing Slim :( and switching to tf.layers and tf.contrib.layers.
Removing Slim :( and switching to tf.layers and tf.contrib.layers.

PiperOrigin-RevId: 204862278

vthorsteinsson/tensor2tensor,vthorsteinsson/tensor2tensor,tensorflow/tensor2tensor,tensorflow/tensor2tensor,vthorsteinsson/tensor2tensor,tensorflow/tensor2tensor,tensorflow/tensor2tensor,tensorflow/tensor2tensor,vthorsteinsson/tensor2tensor