Documenting how to launch multilingual tasks

[clefourrier]

Atm, need to use custom tasks to launch them, must be documented

[ceferisbarov]

Came here to open this issue. It took me some time to figure out that I need to a pass a custom task file and not a folder:

lighteval accelerate "model_name=gpt2" "community|tumlu:azerbaijani|0|0" --custom-tasks .\community_tasks\turkic_evals.py

It would be nice if there was an example like this in README:

[mertbozkir]

+1