Add auto-translation management command

[itsthejoker]

Translation takes a lot of time to find the right people, so it's better to get a jump on it with machine translation than just start without any translations at all, especially for more common languages like Spanish. Investigate:

• https://pypi.org/project/googletrans/
• https://github.com/life4/l10n/blob/master/l10n/_commands/_translate.py