The lexibank.check_languages command should check languages with Glottolog

In order to be able to check against the correct version of Glottolog, either the command should take `--glottolog` and `--glottolog-version` options, or look up the expected Glottolog version in the dataset metadata.

See https://github.com/lexibank/pylexibank/blob/master/src/pylexibank/commands/check_languages.py