new version of Ted Talks IWSLT (WIT3)
In the previous iteration #1608 I had used language pairs. Which created 21,582 configs (109*108) !!! 

Now, TED talks in _each language_ is a separate config. So it's more cleaner with _just 109 configs_  (one for each language). Dummy files were created manually. 

Locally  I was able to clear the `python datasets-cli test datasets/......` . Which created the `dataset_info.json`  file . The test for the dummy files was also cleared. However couldn't figure out how to specify the local data folder for the real dataset


**Note: that this requires manual download of the dataset.** 
**Note2: The high number of _Files changed (112)_ is because of the large number of dummy files/configs!**