Handle emojis in the username

[levnikmyskin]

Currently it's not possible to store username containing emojis in the database. This is due to telegram sending emojis in a utf16 with surrogates encoding (by the way, if you paste an emoji such as \ud83e\udd13 on PyCharm console, it looks like it's going to screw it all up and needs to be restarted).
In python, one could decode it with: s.encode('utf16', 'surrogatepass').decode('utf16')
However the mysqlclient library then crashes. I don't see any solution for this at the moment