Moved password database related efuns to system-module

Rev: src/modules/spider/configure.in:1.14
Rev: src/modules/spider/spider.c:1.22
Rev: src/modules/system/Makefile.in:1.3
Rev: src/modules/system/configure.in:1.5
Rev: src/modules/system/passwords.c:1.1
Rev: src/modules/system/syslog.c:1.2
Rev: src/modules/system/system.c:1.9
Rev: src/modules/system/system.h:1.1