RotatingFileHandler: Let the docstring make sense
RotatingFileHandler: Let the docstring make sense

Having files "app.2.log" and "app.2.log" didn't.

Change-Id: If96617cf7026ca33fded34e8a1f19db882f9b54f

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