callmonitor:
 * fix webui-login-method detection code (the logic shamelessly derived/stolen from the latest demo version of [http://www.telefonsparbuch.de/tmpl/calc/telephone/lcr/info/fritzbox_lcrupdater_download.htm LCR Updater], sorry & thank you Harald)
 * expected to fix "callmonitor could not read AVM phone book on older firmwares"-problem
 * refs #2437


git-svn-id: file:///var/svn/freetz/trunk@12086 149334a1-2f27-0410-a3b9-fc62619ac1e6