listpages.py: fix help on formatting
listpages.py: fix help on formatting

Change-Id: Ib59ba3182130624f01bb4068a2e525c0862e5e11

Darkdadaah/pywikibot-core,magul/pywikibot-core,hasteur/g13bot_tools_new,jayvdb/pywikibot-core,npdoty/pywikibot,PersianWikipedia/pywikibot-core,hasteur/g13bot_tools_new,wikimedia/pywikibot-core,wikimedia/pywikibot-core,jayvdb/pywikibot-core,happy5214/pywikibot-core,Darkdadaah/pywikibot-core,npdoty/pywikibot,magul/pywikibot-core,hasteur/g13bot_tools_new,happy5214/pywikibot-core