[FIX] APISite: Blocked IPv6 usernames in uppercase
[FIX] APISite: Blocked IPv6 usernames in uppercase

The usernames of anonymous users with an IPv6 address are saved with the
letters uppercased. So when querying using such usernames (via bkusers)
those need to be uppercased.

Unfortunately it's possible to fake IPv6 addresses using '::' and those
might have not uppercase letters so it's not uppercasing them.

Change-Id: Iddfb2823cdfae16caa182ba7874beb5a08dd997b

hasteur/g13bot_tools_new,hasteur/g13bot_tools_new,icyflame/batman,darthbhyrava/pywikibot-local,smalyshev/pywikibot-core,wikimedia/pywikibot-core,Darkdadaah/pywikibot-core,trishnaguha/pywikibot-core,valhallasw/pywikibot-core,wikimedia/pywikibot-core,h4ck3rm1k3/pywikibot-core,xZise/pywikibot-core,npdoty/pywikibot,PersianWikipedia/pywikibot-core,magul/pywikibot-core,jayvdb/pywikibot-core,emijrp/pywikibot-core,TridevGuha/pywikibot-core,Darkdadaah/pywikibot-core,happy5214/pywikibot-core,magul/pywikibot-core,h4ck3rm1k3/pywikibot-core,hasteur/g13bot_tools_new,npdoty/pywikibot,VcamX/pywikibot-core,happy5214/pywikibot-core,jayvdb/pywikibot-core