Update Russian websites (#3469)

* category-gov-ru: remove a domain that doesn't belong to a federal city

The domain belongs to the energy company Sapsan Energia.
http://sev.ru/about/

* category-travel-ru: add Othello

The Othello domain is on Sber's list.

* category-bank-ru: add a comment

* mailru-group: add a missing mail.ru email domain

* category-travel-ru: add Fasten

* mailru-group: update comments

* mailru-group: update comments

© My.com, myMail

* category-travel-ru: update Otello

* category-travel-ru: update Otello

* category-bank-ru: add Gazprom ID

data/category-gov-ru

@@ -43,7 +43,6 @@ mos.ru          # Moscow
 mosreg.ru       # Moscow Region
 spb.ru          # St. Petersburg
 sevastopol.ru   # Sevastopol
-sev.ru          # Sevastopol
 
 # Republics
 adygeya.ru      # Republic of Adygea