adding wili-2018 language identification dataset
@lhoestq Not sure what happened, I just changed the py file but it is showing some TensorFlow error now. You can ignore it.
It's caused by the Tensorflow update that happened 30min ago. They added breaking changes.
I'm working on a fix on the master branch right now
 oh okay, btw I have made the required change for reading the CSV, I think it should be fine now, please take a look at it when you have some time. merging since the CI is fixed on master