added div2k import

Author: WilliamHYZhang

tensorflow_datasets/image/__init__.py

@@ -42,6 +42,7 @@
 from tensorflow_datasets.image.cycle_gan import CycleGAN
 from tensorflow_datasets.image.deep_weeds import DeepWeeds
 from tensorflow_datasets.image.diabetic_retinopathy_detection import DiabeticRetinopathyDetection
+from tensorflow_datasets.image.div2k import Div2k
 from tensorflow_datasets.image.dmlab import Dmlab
 from tensorflow_datasets.image.downsampled_imagenet import DownsampledImagenet
 from tensorflow_datasets.image.dsprites import Dsprites