Fix issue generating split on Windows

Bugfix: `medium` and `large` have 0 rows (#1)

with metadata

bug fix

test

test

test

test

new split_generators method to work with the new generate_examples method

new generate_examples method

test without metadata

fix bug (wrong index for speaker_id)

fix bug (typo method)

fix bug (archive path not a dict)

fix bug

fix \

added type for metadata

bug fix

first commit

initial commit