cased -> uncased for example cmdline consistency
In the same file, there is also `--do_lower_case` wrongly apply to `roberta-base` and `xlnet-large-cased` model. It will be great if this PR also includes that fix.<|||||>> In the same file, there is also `--do_lower_case` wrongly apply to `roberta-base` and `xlnet-large-cased` model. It will be great if this PR also includes that fix.

The intention is to have consistency across all the experiments, where all input is lowercase for all examples. Just because roberta and xlnet don't have lowercased models, doesn't mean their input has to be the cased version.<|||||>Thanks for raising this. Should be fixed by #3738

if one saves their tokenizers using `save_pretrained()` there shouldn't be a need for passing the `do_lower_case` manually anymore.