[cleanup] Cleanup sysopnames in config2.py
[cleanup] Cleanup sysopnames in config2.py

config.sysopnames is deprecated since 6f0cafd

- documentation about sysopnames
- move sysopnames to obsolete section
- do not assign families to sysopnames in register_family_file

Change-Id: I43ca15fdb9db60fb65d81354931e80548499fc2a

PersianWikipedia/pywikibot-core,wikimedia/pywikibot-core,wikimedia/pywikibot-core