added auth_user.security_hash virtual field (to validate user_id in public url)
added auth_user.security_hash virtual field (to validate user_id in public url)

tectronics/web2conf,reingart/web2conf_googlecode,tectronics/web2conf,tectronics/web2conf,reingart/web2conf_googlecode,bkahlerventer/web2congress,bkahlerventer/web2congress,bkahlerventer/web2congress,bkahlerventer/web2congress,tectronics/web2conf,reingart/web2conf_googlecode,reingart/web2conf_googlecode