Add OCNLI, a new CLUE dataset
Thanks :) merging it
OCNLI stands for Original Chinese Natural Language Inference. It is a corpus for
            Chinese Natural Language Inference, collected following closely the procedures of MNLI,
            but with enhanced strategies aiming for more challenging inference pairs. We want to
            emphasize we did not use human/machine translation in creating the dataset, and thus
            our Chinese texts are original and not translated.